The catastrophic extinction of North
American mammoths and
mastodonts
Gary Haynes
Abstract
Archaeological and theoretical evidence reviewed here indicates that Clovis-era foragers exterminated mammoths and mastodonts in North America around 11,000 radiocarbon years ago. The
process unfolded quickly as human foragers explored and dispersed into fragmenting habitats where
megamammal populations were ecologically stressed. Megamammal extinctions were eco-catastrophes with major ripple effects on oral and faunal communities.
Keywords
Mammoth; mastodont; extinction; Palaeoindian; North America; patch choice.
Introduction
Mammoths and mastodonts became extinct in North America soon after 11,000 radiocarbon years before present (RCYBP) (Taylor et al. 1996; Martin and Stuart 1995; Stuart
1991). Thirty-three genera of large mammals (body mass over 44 kg) died out around the
same time (Martin and Klein 1984). Distinctive Clovis uted projectile points (Plate 1)
also appeared then (see the papers in Bonnichsen and Turnmire 1991). Prehistorians such
as C. V. Haynes, Jr. [who is not related to me] have proposed that uted point assemblages represent North America’s earliest archaeological culture because they are the
oldest found at virtually every site, locale or subregion where they have been dated. The
exceptions are few, such as in Alaska’s Tanana river valley sites (Hamilton and Goebel
1999) or in scattered locales such as Cactus Hill, Virginia (McAvoy and McAvoy 1997)
and Meadowcroft Rockshelter, Pennsylvania (Adovasio et al. 1999). But examples of preuted-point components are extremely rare (Fiedel 2000). The people who made the
Clovis-type uted points are incontestably the Žrst to arrive in most parts of late Pleistocene North America, and therefore are closely linked chronologically with the disappearance of mammoths and mastodonts.
World Archaeology Vol. 33(3): 391–416 Ancient Ecodisasters
© 2002 Taylor & Francis Ltd ISSN 0043-8243 print/1470-1375 online
DOI: 10.1080/0043824012010744 0
392
Gary Haynes
Plate 1 Fluted point (cast) from the Vail site in Maine. Fluted points
compared over space and time may differ in morphology and manufacturing
techniques.
We know that human hunting can limit or exterminate ungulates with or without
climate stress (Alroy 2000; Kay 1994, 1995; Martin 1967, 1982, 1984, 1990; Martin and
Steadman 1999; Mithen 1993; Stuart 1999). If the Žrst settlers in North America targeted
large mammals as preferred prey, their opportunistic foraging (Kelly and Todd 1988;
Meltzer 1993: 305) may have eradicated mammoth and mastodont populations that had
survived earlier cycles of ecological stress during rapid climatic oscillations (Alroy 1999;
Martin and Steadman 1999).
The removal of mammoths and mastodonts from the New World was an ecocatastrophe that happened swiftly and unexpectedly. Fossils of large mammals show no
evidence of climate-caused chronic ill-health or increased vulnerability just before they
disappeared (see, for example, Fisher (1996) for information about mastodonts and
Duckler and van Valkenburgh (1998) for information about predators). The large
mammals – including mammoths and mastodonts – were exterminated so quickly that the
geological record provides no direct clues about how it happened.
The disappearance of America’s largest forms of animal life would have been a memorable event for humans to experience. As well, the disappearance of animals large enough
to be true ‘ecosystem engineers’ (see Owen-Smith 1987, 1988, 1999) would have had
profound effects on North American ecosystems. Owen-Smith (1987, 1999: 67) has argued
that the extinction of megamammals – the animals weighing over 1,000 kg – transformed
a minor extinction pulse affected by climate change into a major extinction cascade,
because mammoths and mastodonts were ‘keystone’ species that had greatly raised diversity at the patch level. With the megamammals gone, natural processes such as woody
regeneration and shrub invasions of grassy glades progressed unimpeded, thus reducing
carrying capacity for nonmigratory grazers.
Zimov et al. (1995) presented a simulation model showing that the removal of
Beringia’s megafauna by human overhunting was as important as climate in shifting the
vegetation from highly productive, grass-dominated steppe to poorly productive mosstundra. Large herbivore feeding has major effects on ecosystems and is known to increase
primary productivity in African grassland savanna (Bell 1971), an effect also postulated
for California grasslands (Edwards 1992). The process of biome shift due to herbivore
Catastrophic extinction of mammoths and mastodonts
393
feeding is now being observed in Yakutia, where large grazers were recently re-introduced
into tundra-taiga habitats that may be transformed to steppe in the future (Stone 1998;
Zimov et al. 1995: 782–3).
lf human foragers did wipe out mammoths and mastodonts in North America and indirectly caused the extinctions of other animal species, can we ever discover why and how
they managed to do it? My explanation of the process is founded on three propositions:
(1) the timing and direction of climate-caused habitat changes were not coupled with
extinctions; (2) megamammals were demonstrably killed by human hunters in North
America; (3) late Pleistocene foraging in mammoth and mastodont ranges was an optimal
strategy for opportunistic hunter-gatherers. These will now be discussed.
Climate-caused changes in habitat were not coupled with extinctions
At the end of the Pleistocene, severe climate reversals occurred out of phase with the
extinction event. The Younger Dryas chronozone – a northern hemisphere geological
interval of cold that had abruptly reversed warm and wet conditions beginning around
11,000 RCYBP and ending nearly a millennium later (duration and timing are problematical in different world areas (Rutter et al. 2000)) – is sometimes thought to have been the
last straw for larger mammals, killing them off completely after they had suffered through
several cold to warm reversals following the last Glacial Maximum.
Yet the current best-guess chronosequence of events during the glacial to deglacial transition (for example, Fiedel 1999: 106, Žg. 6) does not support this scenario of extinction
based solely on climate. The earliest appearance of foragers who made Clovis uted
points was about 11,500 RCYBP (Fig. 1). Some large mammals may have become extinct
around 11,200 RCYBP, followed by a near-continental drought beginning 10,900 RCYBP,
and the extinctions of all large fauna including mammoths and mastodonts by around
10,800 RCYBP (Graham et al. 1997; Stafford et al. 1997a, 1997b; Holliday 2000; Haynes, C.
V. 1991). The Younger Dryas reversal to cold conditions may not have occurred everywhere, and, where it did occur, it followed some extinctions but preceded mammoth and
mastodont extinction. In southern South America there may have been no Younger Dryas
at all (Bennett et al. 2000; Rodbell 2000), and thus the New World pattern of extinctions
is not a direct result of the abrupt onset or end of the Younger Dryas. It is worth noting
again that megafauna such as ground sloths, horses, camels, mammoths and mastodonts
had universally survived earlier abrupt climate reversals.
No clear model can explain how the extinction process tracked changes in climate and
habitat at the end of the Pleistocene (see Krech 1999: 38–40 for a précis of the ambiguity). But the extinctions do seem to be synchronous with the existence of human foragers
who dispersed through the continent within a few centuries of Žrst appearing.
The Clovis foraging strategy involved killing megamammals
The makers of Clovis-like uted points were present over almost all of North America
south of the last glacial ice-fronts, between around 11,500 and 10,500 years ago (Table 1).
Warm
Cold
Warm
Cold, drier
Cold continues
Warm, wetter
12,000
11,500
11,200
10,900
10,800
10,200
(No extinctions)
(No extinctions)
(No extinctions)
(Unnamed
Some large-mammal
warm interval) extinctions
Younger Dryas
begins abruptly
All megafauna
extinctions complete,
including mammoths
and mastodonts
Younger Dryas
ends abruptly
Intra-Allerød
cold period
Allerød
Bølling
Chronozone or Faunal Event
Event
Last Glacial
(No extinctions)
Maximum
Figure 1 Correlation of climate changes, hypothesized extinction events and culture in North America.
Warm
13,000
Climate
Very cold, dry
years B.P.
19,500-16,100
14C
Fluted points no longer
made
(Archaeological
remains rare to
nonexistent anywhere
in continent)
(Archaeological
remains rare to
nonexistent anywhere
in continent)
(Archaeological
remains rare to
nonexistent anywhere
in continent)
Earliest Clovis
radiocarbon dates, very
restricted range
Clovis present in wide
area
Clovis becoming locally
more variable
Clovis-like materials
distributed continentwide
Cultural Event
Catastrophic extinction of mammoths and mastodonts
395
A small but inuential literature has argued that Clovis uted point makers were big-game
hunters, directly descended (biologically and culturally) from Eurasian Upper Palaeolithic steppe explorers (see, for example, Haynes, C. V. 1987). Scholars who accept this
probable connection nevertheless recognize that smaller game and plant resources also
would have been eaten (Jennings 1989; Willey 1966).
On the other side of the debate are arguments that only plants and small animals were
regularly targeted as food, in direct proportion to their existence in Clovis-era habitats
(Dent 1995; Dincauze 1993: 285; Meltzer 1993; Meltzer and Smith 1986). The hypothesis
that Clovis foragers were mainly plant-food gatherers and smaller-game hunters implies
that Pleistocene large mammals were either hunted extremely rarely, especially if populations were dwindling due to climatic stress (Webster and Webster 1984), or were deliberately avoided. The sites where Clovis tools are associated with megamammal skeletons
(see below) are therefore considered more likely the evidence of scavenging rather than
of killing.
However, a comparison of the characteristics that distinguish killing from scavenging
(Haynes, G. 1999) indicates some Clovis mammoth associations are cases of actual
killing, after all. The basis for comparisons are studies of contemporary bonesites where
African elephants were either shot to death or starved during droughts in Zimbabwe
Table 1 Generally accepted radiometric dates on Clovis-point sites (from Holliday 2000; Haynes,
C. V. 1993; Taylor et al. 1996).
Site
Date(s)
Material dated
Anzick, MT
Aubrey, TX
Clovis type site
(Blackwater Draw, NM)
Colby, WY
Average of 3 = 10,820 ± 60
Average of 2 = 11,570 ± 70
Average of 2 = 11,130 ± 90
Average of 3 = 11,300 ± 240
11,200 ± 220(RL-392)
10,864 ± 141 (SMU-264)
Average of 13 = 10,590 ± 50
Average of 5 = 10,690 ± 50
plus 11,200 ± 500
Average of 2 = 10,820 ± 230
Other averages 11,040 ± 250
and 10,940 ± 180
11,140 ± 140(AA-905)
10,730 ± 530 (I-13104)
Average of 12 = 10,930 ± 40
Average of 8 = 10,900 ± 50
Average of 2 = 10,640 ± 90
Average of 2 more = ~10,900
10,190 ± 300 (W-3931)
7 dates, 11,120 ± 180
to 10,040 ± 390
Average of 2 = 11,050 ± 300
(2 other parts of the site were
dated 9,400 ± 500 to
10,430 ± 300)
Bone
Charcoal
Plant remains
Plant remains
Bone apatite
Bone collagen
Charcoal
Bone
Debert, Nova Scotia
Dent, CO
Domebo, OK
Lange/Ferguson, SD
Lehner, AZ
Murray Springs, AZ
Shawnee-Minisink, PA
Templeton, CT
Vail, VT
Whipple, NH
Carbonized plants
Bone collagen and gelatin
Bone collagen and gelatin
Charcoal
Bone collagen
Charcoal
Charcoal
Charcoal
Charred hawthorne plum seeds
Charcoal
All but one on charcoal;
youngest date on humates
Charcoal
(Charcoal)
396
Gary Haynes
(Haynes, G. 1987, 1988, 1989, 1991). The modern sites are similar in some ways but
distinct in other subtle ways (see Haynes, G. 1999; Haynes, G. and Eiselt 1999) (Table
2). If bone representation, weathering stages, carnivore utilization and mortality proŽles
are compared between cultural killsites and noncultural deathsites, the modern sites of
elephant bones differ to perceptible degrees when their origins differ. The presence or
absence of artifacts is not the deŽning characteristic that sets apart cultural and noncultural deaths.
An examination also has been made of Columbian and woolly mammoth bone assemblages (Haynes, G. 1999). The differences among the sites suggests unambiguously in
some cases and ambiguously in others that human behavior created certain sites and
natural (noncultural) processes created others, even those with clearly associated artifacts. This evidence does therefore support the idea that Clovis foragers actually killed
mammoths individually or in groups.
Empirical and analogical approaches to explaining the role of megamammals in Clovis
diets
Opinions differ about Clovis subsistence and diet because the methods of reconstructing
the possible diet of uted point-makers rely on three distinct lines of evidence: empirical
data, ethnographic analogy and theoretical predictions. The three approaches produce
different interpretative results.
(a) Empirical evidence Plant and animal remains are scarce at Clovis uted point sites.
Yet at least twenty sites contain mammoth or mastodont bones (Table 3) either directly
associated with uted points or interpreted as butchered during the Clovis period. The
remains of animals other than proboscideans in direct stratigraphic and spatial association
with uted points are less abundant (Table 4). Many sites contained no more than teeth
or a single element or bone fragment of camel, caribou or other large mammal. Several
Table 2 Comparison of cultural and noncultural elephant bone accumulations.
Variable examined
Serial deaths only
Cultural origin
Noncultural origin
Carnivore use
Weathering
Bone representation
Age proŽle
Often light
Mixed
Selective
Varies
Varies
Mixed
Nonselective
Selective
Variable examined
Mass deaths only
Cultural origin
Noncultural origin
Carnivore use
Weathering
Bone representation
Age proŽle
Light to moderate
Mostly similar
Nonselective
Nonselective
Light to moderate
Mostly similar
Nonselective
Selective
Catastrophic extinction of mammoths and mastodonts
397
Table 3 Mammoth (Mammuthus columbi) and mastodont (Mammut americanum) sites with Clovis
association, or dated to the Clovis time interval. (Note: Fisher (1996) names other late Pleistocene
mastodonts he considers butchered by humans in the Great Lakes region, but here I list only two,
Heisler and Pleasant Lake in Michigan.)
Site
Taxon and number
of animals present
Cultural association/date
Blackwater Draw, NM
Burning Tree, OH
Mammoth, 6
Mastodont, 1
Colby. WY
Mammoth, 7
Dent, CO
Mammoth, 13
Domebo, OK
Dutton, CO
Escapule, AZ
Heisler, MI
Mammoth, 1
Mammoth, 1
Mammoth, 1
Mastodont, 1
Hiscock, NY
Mastodont, 6
Kimmswick, MO
Lange-Ferguson, ND
Mastodont, 2
Mammoth, 2
Lehner, AZ
Leikum, AZ
Lubbock Lake, TX
Miami, TX
Murray Springs, AZ
Naco, AZ
Navarettej AZ
Pleasant Lake, MI
Mammoth, 13
Mammoth, 2
Mammoth, 2(?)
Mammoth, 5
Mammoth, 2
Mammoth, 1
Mammoth, 1
Mastodont, 1
Rawlins, WY
(U.P. mammoth)
Mammoth, 1
Clovis lithics; averaged 3 dates 11,170 ± 110
No lithics, possibly butchered bones; 10,860 ±
70 (Pitt-0832) and 11,390 ± 80 (AA-6980)
Clovis lithics; 11,200 ± 220 (RL-392) and
10,864 ± 141 (SMU-254)
Clovis lithics; averaged 5 dates 10,690 ± 50, and
11,200 ± 500
Clovis lithics; averaged 2 dates 10,820 ± 270
Clovis lithics; <11,710
Clovis lithics; no date
No lithics, possibly butchered bones; 11,770 ±
110 (NSRL-282, AA-6979)
Clovis lithics; 11,390±80 (AA-6977) to 10,515 ±
120 (Beta-24412)
Clovis lithics; no date
Clovis lithics; 11,140 ± 140 (AA-95) and 10,730
± 530 (I13104)
Clovis lithics; averaged 12 dates 10,930 ± 40
Clovis lithics; no date
Clovis lithics; >11,100
Clovis lithics; no date
Clovis lithics; averaged 8 dates 10,970 ± 50
Clovis lithics; no date
2 Clovis points; no date
No lithics, possibly butchered bones; 10,395 ±
100 (Beta-1388)
Untyped lithics; 11,280 ± 350 (I-449)
Note: Occasionally other megamammal Žnds with possible Clovis associations have been dated
radiometrically well older or younger than Clovis. These examples can be partly explained by the
nature of radiocarbon dating – ‘dates’ are only a statistical probability of an object’s age and not a
simple ‘fact’ – or by the potential for sites, sediments and samples to be contaminated, or by inappropriate choices of materials to be dated, or by ‘associations’ that are speculative rather than clearly
demonstrated, etc. At least one-half of all radiocarbon dates returned over the past half-century
probably have been rejected or suppressed because of suspected errors. This may make readers
nervous that the real dates of Clovis and megamammal extinction could be quite different from the
11,500–10,500 radiocarbon years generally accepted. However, when samples are carefully collected
and lab protocols followed, the dates much more often come out within the generally expected time
interval (see Stafford 1988; Stafford et al. 1987, 1988).
studies have been interpreted to indicate that large mammal blood, including that of
mammoths, was present on some uted points (Table 5).
Hence, the evidence for megammamals in the Clovis diet is ample, but the evidence for
food items other than megamammals is scarce. Botanical macrofossils are even more rare
398
Gary Haynes
Table 4 Sites with possible associations of Clovis artefact(s) and animals other than mammoth or
mastodont. ‘Clovis lithics’ refers to assemblages containing both Clovis uted points and other stone
implements. Not all taxa in the table should be considered food items, and many may be ‘background’ accumulations. Many taxa were represented by only small numbers of bones or teeth. Some
sites contained mammoth or mastodont bones, too.
Site
Cultural association
Taxa
Aubrey, TX
Clovis lithics
Blackwater Draw, NM
Bull Brook, MA
Colby, WY
Escapule, AZ
Hiscock, NY
Clovis lithics
Clovis lithics
Clovis lithics
Clovis points
Clovis points
Holcombe, MI
Kimmswick, MO
Lehner, AZ
Clovis lithics
Clovis lithics
Clovis lithics
Murray Springs, AZ
Clovis lithics
Naco, AZ
Shawnee-Minisink, PA
Sheriden Cave (or Pit), OH
Deer, bison, rabbit, muskrat, Žshes, birds,
turtles, rodents, ground sloth (skin only)
Bison, horse, camel, box turtle
Caribou, beaver
Hare, pronghorn, ass, camel, bison
Horse
Caribou, moose/stag-moose, California
condor, grebe
Caribou
Micromammals (mainly rodents)
At least 11 taxa, incl. micromammals, and
horse (teeth), camel, bison
Numerous taxa, incl. micromammals, and
horse (teeth), camel, bison
Bison
Fish, micromammals and reptiles
Turtle, caribou, peccary, giant beaver
Clovis points
Clovis lithics
Clovis lithics
(Holcombe-like point)
Nondiagnostic cached Cervid, hare, arctic fox
lithics, plus nearby
surface Clovis
(Gainey?) points
Clovis lithics
Caribou
Udora, Ontario
Whipple, NH
Table 5 The results of blood residue studies on Clovis tools. 1. Gramly (1991, 1993).
2. Hyland et al. (1990); one endscraper out of forty-Žve tested had cervid residue. 3. Dixon (1993);
Loy and Dixon (1998). 4. Kooyman et al. (2000). 5. Brush and Yerkes (1996); Brush and Smith
(1994); Brush et al. (1994). 6. Molyneaux (2000).
Site (reference)
Taxa identiŽed
East Wenatchee (Richey-Roberts), WA (Clovis cache) (1)
Human, bison, bovine,
cervid, rabbit
Cervid
Mammoth
Bovid, horse
Elephant, cervid
Shoop, PA (l endscraper tested in Clovis site) (2)
Alaskan uted points (3)
Wally’s Beach, Alberta (Clovis points) (4)
Martins Creek, OH [note: not a proven Clovis site; site contains
mastodont and deer bones associated with akes and scrapers] (5)
Western Iowa (Northern Loess Hills) (6)
Cervid
Catastrophic extinction of mammoths and mastodonts
399
than small animal remains, and thus very few plant foods are known. Nuts, grains, and
perennial roots or tubers require special tools and technologies such as milling stones or
rock-lined roasting pits, which are virtually nonexistent in Clovis times (Table 6).
Faced with a disappointingly small proportion of sites that indicate anything about diet,
some prehistorians bypass the continent-wide empirical evidence and invent site-by-site
diets based on what might have been possible. However, judging only on the basis of
recovered materials rather than on the basis of possibilities, the logical conclusion is that
uted point makers ate megamammals more frequently than anything else known.
(b) Ethnographic analogy Another argument made against megamammal-hunting by
Clovis is based on ethnographic literature. There are no known subsistence hunters of
megamammals in the world nowadays, except for arctic native whalers. In Africa,
elephants are still killed by ivory poachers or people seeking both trade items and food
(Fisher 1987, 1992; Duffy 1984); but no longer is meat the main reason for killing elephants
in Africa (Sikes 1971: 309–10). Modern subsistence foragers – even those in elephant
country – target medium and small game, and rely more on plant foods than on game
animals (Lee 1968; see also Meltzer 1988, 1993). Some archaeologists interpreting Clovis
subsistence have relied on ethnographic analogues to develop a line of reasoning that
Clovis uted point makers, like modern foragers, also never or rarely tried to kill megamammals, and instead chose to forage for a wide range of smaller game, plant foods and
aquatic resources (Dincauze 1993; Meltzer 1988, 1993). Tacit in this argument is the idea
that foragers procure different food resources in the same proportions the resources occur
in local environments. Because there are more smaller animals than megamammals in
terrestrial habitats, more small animals would have been hunted.
Anthropology’s available ethnographic snapshots are of foragers who no longer live in
a world of foragers, and they behave differently from foragers who did live in such a world,
where the ability to disperse, explore and exploit resources was less limited (for an
example of differences between modern and prehistoric foragers, see Sealy and Pfeiffer
2000). One major difference between Pleistocene and recent foragers has been shown in
a study of human bones from two late Pleistocene sites in England: analysis of the bones
Table 6 Clovis sites with milling stones, roasting pits or other tools/facilities suggesting routine use
of nuts, seeds or other plant foods. 1. Hester (1972: 107–9). 2. MacDonald (1968: 111, table 15). 3.
Spiess and Wilson (1987); Dincauze (1993).
Site (reference)
Artifact/facility present
Comments
Blackwater Draw, NM (1)
One grinding stone (‘small mano’)
Debert, Nota Scotia (2)
Possible processing implements:
‘pulping planes, cleavers’
Michaud, ME (3)
Possible processing implements:
cobbles
Used for pounding and
reciprocal grinding; not known
if used for seed preparation or
intknapping
Suggested use: processing
vegetable products for food or
fuel
Possibly used for grinding,
pounding, plant processing
400
Gary Haynes
shows that the diet at around 12,000 RCYBP consisted mainly of terrestrial animal meat
(Richards et al. 2000), unlike the diet of modern foragers which tends to be mostly plant
foods (see Lee 1968).
Late Pleistocene foraging in North America would have been distinct from the behavior of modern foragers in other ways, as well. During the late Pleistocene, megamammal
kills would have been naturally refrigerated or frozen for long periods of time and thus
would have ‘kept’ much better than do elephant carcasses in tropical or subtropical Africa
and Asia; the preservation would have facilitated a much more efŽcient use of huge
carcasses. Perhaps the convenience of long-term storage encouraged regular hunting of
bigger animals.
Modern-day ethnographic analogy cannot reliably predict Clovis foraging or subsistence behavior. Clovis foragers colonized an enormous, highly diverse continent with an
extremely low human population density, if it had any humans in it at all. Clovis foraging
probably differed from tropical foraging in so many ways that analogies should not be
trusted when reconstructing Clovis diet.
Human nutritional requirements are satisŽed by a great many alternative diets. Speth
and Spielmann (1983) demonstrated that high-protein diets (such as from megamammal
hunting) require animal fat or carbohydrates to supplement lean meat, otherwise humans
would die from protein poisoning or suffer chronic disease. However, even food-stressed
mammoths and mastodonts would have provided relatively large packages of fat and
meat, some of the fat distributed around the meat, some around viscera and some within
bone marrow cavities (Haynes, G. 1991, unpubl. Želd notes 1982–7). Megamammal
hunters or scavengers would have eaten adequate fat from each megamammal carcass,
and avoided protein poisoning.
Recent optimal hunter-gatherer diets are modeled as healthy mixtures of plant and
animal foods low in fat (Eaton et al. 1997), considered to be an evolutionary ideal. Thus
a diet high in megamammal meat and fat may not sound very healthy from the modern
perspective, but even a human diet that is ‘high in animal fat and low in vegetable-derived
foods is not incompatible with [good] health’ (Johns et al. 2000: 458), according to a recent
study of a non-industrialized society. This study suggests that megamammal-hunters
would not have been plagued by high cholesterol or other potential problems simply
because they ate minor amounts of plant foods with their mammoth meat, if they supplemented their diet with select roots, gums, resins or barks that provide antioxidants and
blood lipid-lowering phytochemicals (Johns et al. 1999, 2000).
Finally, as a last rebuttal against using ethnographic analogies to reject Clovis hunting
of mammoths, I submit that to argue about the impossibility of megamammal hunting
based on the dangers of such a practice is by far the most defective kind of reasoning. A
lesson may be learned by reading George Catlin’s eyewitness description of a Plains
Indian buffalo surround which turned into ‘a grand turmoil’ and ‘desperate battle’ (Catlin
1989 [1844]: 196, 197) between Minataree hunters and ‘infuriated’ buffalo: unhorsed men
ran for their lives in front of pursuing bulls, and hunters leapt from their horses onto the
backs of thronging buffalo to escape a crush. These explosive activities were regular
occurrences for native American buffalo hunters. Clearly the Minataree hunters Catlin
watched were courageous beyond the limits that archaeologists Žnd in themselves. Likewise, few if any archaeologists will venture into Arctic waters in a skin boat to go whaling,
Catastrophic extinction of mammoths and mastodonts
401
armed with only throwing-boards and harpoons, but arctic native peoples often did so
(Yesner 1980), knowing full well the risks. As a native whaler from the Chukotka region
of Russia told Makah whaling captain Wayne Johnson, ‘Not everyone’s going to come
home all the time [from a whale hunt]’ (Sullivan 2000: 52).
Killing megamammals was optimal foraging at the end of the Pleistocene
The marginal value theorem has been mistakenly interpreted to predict that disappearing species would not have been hunted since they were harder and harder to locate
(Webster and Webster 1984; Meltzer and Smith 1986). Based on this reasoning, and taking
into account the ethnographic snapshots of foraging behavior mentioned above, an argument has been made that uted point makers did not preferentially hunt mammoths and
mastodonts.
However, the marginal value theorem (MVT) does not directly predict that foragers
reduce their value ranking of a dietary item based exclusively on that item’s scarcity
(Charnov 1976; Winterhalder 1981). What the MVT does predict is how foragers evaluate the time spent in a patch looking for food before leaving to seek food in other patches
(Fig. 2). Studies of modern foragers show that patch-residence time may increase during
periods of climate change, gradual overhunting or forager population growth, because,
once foragers become aware that prey abundance is falling, they no longer see good
reasons to seek another patch whose prey abundance is also likely to be dropping. Hence,
prey depletion may continue in the very patches where hunting pressure is already high
(see Smith and Wishnie 2000). Foragers under these and other conditions make subsistence decisions to maximize the harvest of energy per time spent foraging, in spite of possible depletion effects on prey, because proŽtability is the routine goal of foraging – even
when it furthers prey depletion (Smith and Wishnie 2000).
Mammoths and mastodonts were highly ranked food resources whose presence could
be plainly predicted in speciŽc ranges, and whose condition and health could be monitored by uted point makers. The presence and the health of megamammals are recorded
through observations of the animals and the abundant signs left by them. Like elephants,
mammoths and mastodonts would have been great trailmakers and sign-leavers (Plate 2).
Modern research on elephants in the wild often relies on studies of dung and other signs
to provide data about elephant numbers, diets and health, and the proportions of animals
of different ages and sexes (Barnes and Jensen 1987; for examples, see De Boer et al. 2000;
Theuerkauf and Ellenberg 2000). Prehistoric foragers would have been skilled trackers
and interpreters of the megamammal landscape.
Food ranking by foragers reects more than a food item’s abundance – it reects energy
return, handling time, reliability, and risk minimization. Certainly Clovis foragers did understand how scarce big animals may have been, but this was not the primary consideration when
deciding to hunt them. Slow-reproducing resources whose local replacement in patches is
perceived as lower than the rate of return from foraging in general will still be harvested,
even at unsustainable rates (Clark 1973; Alvard 1998). Although search time may be high,
larger animals are rationally ranked highly due to the promise of rich return. For example, a
4,000kg mammoth would have returned about 5,000,000 Kcal of energy (calculated based on
402
Gary Haynes
Figure 2 Marginal value theorem (redrawn from Charnov 1976). The chart shows graphically that
a forager who travels a long time to get to a patch will probably decide to stay longer in the patch
than a forager who travels a short time. The decision about how long to stay is made based on the
patch’s rate of return compared to the average rate of return for all patches.
a ratio of 30 per cent body mass salvaged by butchering, and an average value of 4 Kcal per
gram of meat [protein]). The next largest mammal of the times, bison, would have returned
only a quarter of this amount, but may have been no less dangerous to attack. Instead of
spending three days hunting down and processing a bison, optimizing foragers might have
chosen to spend twelve days Žnding and processing one mammoth.
Foragers continually evaluate the potential returns from the animals encountered and
– as has been demonstrated empirically – reasonably rank the bigger ones highly, if there
is a chance of successfully procuring them. Foragers such as those of the late Pleistocene,
who were capable of killing megamammals throughout their ranges, would not have
avoided killing mammoths or mastodonts when encountered, even though these animals
were not always relatively abundant or evenly distributed in their ranges.
Pleistocene foragers evaluated their food returns patch-by-patch in the same manner
as do foragers in modern times – by reference to average returns from all destination
patches (Fig. 2; see Giraldeau 1997). Prior information about resources, prey and the
environment is used in making foraging decisions, and the more promising patches are
searched for longer times than poorer patches, especially if they are widely separated. If
Catastrophic extinction of mammoths and mastodonts
403
Plate 2 An elephant trail
in Kalahari sands of
Africa. Trails are rich
sources of information
about animal numbers,
health and behavior, plus
they make exploratory
travel by human foragers
easier and less risky.
the richer patches also happened to be the places where megamammals aggregated, these
patches would have remained attractive to foragers for relatively long spans of time.
A strategy for reducing search time would have been apparent to foragers in the late
Pleistocene, if megamammal behavior resembled that of modern megamammals such as
elephant and rhinoceros. Foragers of the late Pleistocene, in order to minimize risk, to
increase encounter rates, to reduce pursuit time, and to limit their foraging radius, therefore would have actively sought out the very patches where megamammals aggregated .
A tremendous advantage that humans have over other animal foragers is that they are
omnivorous – they could have comfortably survived in any season by eating a wide variety
of other foods while continuing to search for the preferred megamammal prey, even after
404
Gary Haynes
mammoths and mastodonts had become scarce due to climate change and overhunting
(Owen-Smith, N. 2001 pers. comm.).
If uted point makers (1) did hunt megamammals, (2) did not avoid hunting them when
extinction began to occur and (3) ate megamammals more than other animal and plant
foods, what could be concluded about their continent-wide subsistence preferences? The
answer would be that Clovis people preferred to hunt mammoths and mastodonts, and
that as foragers their mobility strategies were intended to increase the chances of encountering these megamammals. In other words, in this model Clovis subsistence was an
opportunistic specialization in proboscideans.
Foraging specialization in a few, preferred resources is a viable strategy when prey
diversity is low, and prey tend to aggregate in herds that feed nomadically. In the last
deglaciation interval, the largest mammals were distributed non-randomly in different
habitats. Not only were megamammals found in clustered aggregations, but they also were
re-ordering their range distributions as climatic changes forced oral communities to
change their spatial extents and distributions. The main changes in vegetation involved a
reduction in mosaic cell sizes (discussed below) or the areal extent of different oral
communities contacting each other.
Patch dynamics in the late Pleistocene
At the end of the Last Glacial Maximum (LGM) many of the once associated animal
species radically (and individually) rearranged their geographic distributions in response
to changing climatic factors (Graham and Lundelius 1984; Graham et al. 1996). Some
species retreated south, some retreated north and some changed their elevational distributions. Thus ended the existence of Pleistocene ‘mosaics’ of mixed species that do not
live together now.
In many parts of North America the areas of Pleistocene plant mosaics became more
and more separated from each other (King and Saunders 1984), as a result of the postLGM establishment of broad zones of uniform vegetational types, where biotic diversity was much diminished. The last mosaic areas (woodland abutting steppe near
shrubby taxa, for example) had a very reduced distribution at the end of the Pleistocene, particularly in localities such as southeastern Arizona, southern Nevada, central
Mexico, the Great Lakes region, parts of the Ohio river drainage in Kentucky, and
along the limestone-lined floodplains of the Mississippi river in Missouri, all of which
are rich fossil-collecting regions that used to be late Pleistocene refugia. The word
refugium here is used in the sense of ‘an isolated habitat that retains the environmental
conditions that were once widespread’ (Lincoln and Boxshall 1987: 326) and is not the
same as ‘refuge’, which refers to space where predators can be avoided (Lincoln and
Boxshall 1987: 326).
Keystone megamammals in refugia kept biotic diversity relatively high, due to the
major impacts of their feeding, trampling and wallowing habits (Laws et al. 1975; OwenSmith 1987, 1988; Putschkov 1997; Sikes 1971; Western 1991, 1989). Like modern
elephants, American mammoth and mastodont populations may have been able to sustain
densities of up to two or three individuals per 2km, greater than most other herbivores
attain (Owen-Smith 1988, 1999). As Owen-Smith has argued, high densities contributed
Catastrophic extinction of mammoths and mastodonts
405
to megamammal ecosystem engineering – such as the pruning of woody plants during
feeding, the enlargement of water holes and mineral licks, and the suppression of Žres by
opening up vegetation patches.
Hence, once climate changes following the Last Glacial Maximum caused extreme
shrinkage of mosaic cells and the wide separation of once-abutting vegetational patches,
the diversity and productivity of Pleistocene habitats were dramatically changed. Each
different type of cell became isolated, greatly reduced or eliminated. Fewer patches of
rich ecotones survived over time. The ranges of grazing and browsing animals were widely
separated from each other, except in the refugia which continued to provide a variety of
palatable and preferred forage (Fig. 3). Around 11,000 RCYBP, biotic responses to climate
change occurred within even shorter spans of time than before, swiftly destabilizing
ecosystems (Ammann et al. 2000).
Other climatic/palaeoenvironmental trends also served to cluster and isolate the largest
Figure 3 Schematic map showing two diverse mosaic environments separated by zonal vegetation
that herbivores Žnd unpalatable or unpreferred. Terminal Pleistocene refugia may have been
mosaics like these.
406
Gary Haynes
terrestrial mammals at the end of the Pleistocene. A Clovis-era drought of about 10,900
to 10,650 RCYBP (Haynes, C.V. 1993, 1991) or slightly later (Holliday 1997, 2000) forced
mammoths and other large mammals to congregate at a much reduced number of sources
of water and forage (see Haynes, C.V. 1984, 1991) in the American West and possibly
other regions. Research in the mid-continental Great Lakes region similarly indicates that
terminal Pleistocene refugium patches existed there, too, providing either better food,
more of the essential dietary minerals or some other requirement in quantities or quality
higher than in the surrounding regions (Dreimanis 1967; Fisher 1996). The Hiscock site
in northern New York state (Laub 1994; Laub et al. 1988, 1994) contains evidence of
lowered water table at the time mastodonts were dying-off there (c. 10,800 RCYBP.). Wells
were apparently dug by mastodonts seeking clean water; tusk-tips were broken off during
Žghts over access to the wells (Laub and Haynes 1998; see Haynes, G. 1991: 126–31). The
lowering of water tables resulted either from drought or from changes in Great Lakes
hydrology, as the Lakes switched drainage between the St. Lawrence and the Mississippi
river systems during deglaciation. At this same time, in the southern part of the continent
along the coastal plain adjacent to the continental shelf– such as in Florida – water tables
rose as sea levels came up, but the addition of so much water to relatively at land surfaces
created stresses similar to the removal of water in other regions, as the plant forage
drowned or died from waterlogging.
Thus ecological stresses and selective disadvantages existed in mammoth and
mastodont populations during the difŽcult time following the Last Glacial Maximum, and
the stresses intensiŽed after 11,000 RCYBP due to rapid climatic reversals, increased
seasonality and extremes of seasonal climate patterns, and a severe reduction of preferred
habitats. Similar disadvantages can be seen in recent Želd studies of large mammals in
fragmented and crowded ranges (Owen-Smith 1982, 1988; Rachlow 1997; Rachlow et al.
1998). Large mammals suffer from (1) increased incidence of oftentimes violent agonistic encounters; (2) heightened feeding competition leading to mortality of youngest
animals Žrst; and (3) differential reproductive success, as some males successfully breed
but others do not, resulting in a reproduction rate much lower than predicted based on
numbers of animals alone.
Yet, climate change and resultant stresses could not have been the cause of all extinctions. Megafaunal taxa during the Pleistocene partitioned resources and had stereotyped
diets. For example, the Florida mastodonts were browsers while mammoths were grazers,
a conclusion based on geochemistry, habitat reconstructions and the obvious differences
in tooth morphology (Hoppe et al. 1999; Koch et al. 1998). Animals with different stereotyped diets were not uniformly affected by the vegetational changes resulting from the
late Pleistocene climate oscillations. Some animals suffered from disappearing forage, but
other taxa were favored by changes in plant distributions. For example, Florida’s woodlands did not disappear at the end of the Pleistocene, but its browsing mastodonts did,
and it is difŽcult to explain these out-of-phase phenomena without invoking some agent
of mastodont extinction other than habitat change. The late Pleistocene was hard on
mammoths and mastodonts, yet no compelling evidence exists from the very end of the
Pleistocene that both mammoth and mastodont populations suffered greater stress than
they had during earlier climatic oscillations.
Megamammals were not just circling the drain before they went down the plughole of
Catastrophic extinction of mammoths and mastodonts
407
extinction, although they were less abundant than they had been earlier. How did Clovis
foragers respond to the changes in proboscidean vulnerability, distribution, density and
behavior? Under the palaeoenvironmental conditions of the end of the Pleistocene, the
uted point makers preferentially began to hunt megamammals, seeking them out
through patch choices that targeted refugia and high-diversity ecotones. Under the
conditions of the end of the Pleistocene, megamammal-aggregation locales would have
been preferentially sought for foraging.
Clovis ecology, diet and mammoth-hunting
At the level of the entire continent, uted point makers hunted mammoths and
mastodonts in the remnant megamammal refugia. As presented here, a model of contingent causality explains uted point subsistence, settlement and dispersal in terms of late
Pleistocene climatic change, palaeoenvironmental developments, megamammal behavioral patterns and rational foraging decisions. The necessary and sufŽcient causes were
serial in occurrence:
The Žrst event A was the climate-driven changing of late Pleistocene habitats, creating
isolated refugium patches for megafaunal populations. Early human foragers who hunted
medium to large animals such as camels or horses found them easier to locate and kill.
Clovis technology – blades, bifaces and uting – developed under changing ecological
conditions.
Event B was the exploratory dispersal of uted point makers into ranges where
mammoths and mastodonts could be found. Resources were predictable in certain
patches, and the technology created in response included well-prepared and sturdy tools.
Long-distance import of high-quality raw materials raised the cost of the technology, but
the practice of lithic caching helped reduce the high costs of tool transport. Megamammals were preferred prey; niche width was narrow, since diet breadth was deliberately
reduced. Risks were minimized over the long and short terms. The ability to explore and
disperse into new ranges was unlimited.
Event C was the intensiŽed hunting (and scavenging) of mammoths and mastodonts,
along with even wider exploration and dispersal. Overall, the foraging ecology of the Žrst
uted point makers was continentally almost uniform, but the uniformity was overlain by
regional and local variability.
After megamammals became extinct, a new strategy was devised by human foragers.
Resources had become less predictable, and new patches and food resources had to be
found through far less exploration. Lighter-weight tools were manufactured in some
regions, designed to be functionally exible and generalized. Diet breadths were much
wider. This strategy served better in Holocene zonal habitats and the closed woodlands
of the eastern continent.
The colonization eco-catastrophe: extinction of megamammals
In summary: (1) Megamammals were ranked very highly for inclusion in the diet of uted
point makers. Several factors interacted to encourage high ranking: (a) prey body size was
408
Gary Haynes
large, promising hunters huge nutrient returns; (b) migration trails created by megamammals in all likelihood were clear, abundant and Žrmly established in megamammal
ranges, thus prompting human travel and exploration along the same trails that
mammoths, mastodonts and many other mammalian species traveled; (c) late Pleistocene
climatic changes had comprehensive ill-effects on megamammal behavior and biology,
working to the advantage of predatory human groups (cf. also Stuart 1991).
(2) Late Pleistocene refugia were actively sought by Clovis people who used mammoth
and mastodont trail networks, and were visited either serially or sequentially. By seeking
the refugia along established animal trails, uted point makers provided themselves a
cost-reducing and risk-minimizing tactic that supported dispersal widely but safely, and
lessened the uncertainties of exploring unfamiliar territory so quickly. It is also conceivable that human foragers widened their exploratory abilities and improved their foraging
success by establishing partnerships with other hunters and scavengers, such as ravens or
wolves, as they learned how to locate each other and discovered new clues pointing to
hidden game or scattered carcasses (see, for example, Heinrich 1991, 1999).
Megamammals were pursued when encountered and were killed or scavenged. The
empirical and analogical evidence from major sites supports the interpretation that actual
killing of mammoths and mastodonts took place both serially (over short time spans) and
en masse (Haynes, G. 1999). Mithen (1993) computer-modeled mammoth predation
under a variety of environmental conditions and showed that even relatively low levels of
killing by humans would eradicate mammoth populations. The special point I am making
here is that hunting pressures by humans were more than merely minimally sufŽcient to
trigger extinctions, and that, in the absence of human hunting, mammoths and mastodonts
were capable of recovering from the habitat changes, as they had done during earlier
climate-change intervals.
(3) Fluted point foraging was not a ‘generalist’ strategy. It was specialized, meaning that
niche width was preferentially narrow. However, diet breadth was rationally determined
from site to site, and prey switching undoubtedly occurred when necessary. As alternatives to megamammals, other foods such as small animals, plants, and aquatic resources
were procured after active searching, although less readily than the higher-ranked large
mammals.
Once mammoths and mastodonts were removed from North American ecosystems,
several critical ripple effects would have been seen in ecosystems. First, the New World
lost its best trailmakers, whose trail networks had linked optimal resource areas within
ecozones and connected the different zones themselves across the entire continent. Many
animal taxa would have followed these trails, including migrant foraging humans. The
trails linked water sources, fruit and mast patches, mineral licks and optimal feeding tracts
where other ungulates also fed.
Second, megamammals had pruned woody vegetation around wetlands and stream
valleys, thereby incidentally increasing biotic productivity. Megamammals would have
trampled back encroaching woody plants around meadows and grassy glades, keeping the
open vegetation available for nonmigrating grazing mammals. Proboscideans probably
helped create grassy glades where nonmigrating feeders congregated (Guthrie 1984;
Owen-Smith 1987, 1999). Of the taxa that became extinct at the end of the Pleistocene,
many were nonmigrating grazers and browsers of open country (Owen-Smith 1999). After
Catastrophic extinction of mammoths and mastodonts
409
herbivore numbers dropped and the woody plants increased, larger-scale Žres would have
become more frequent, further altering American ecosystems on the patch-scale level and
above.
Megamammals had many other deep effects on ecosystems. They had deepened and
expanded ponded water sources, mineral licks and seepage springs through trampling,
digging and wallowing. After extinction, these types of sites would have been much more
prone to inŽlling through colluvial and alluvial processes, thus reducing surface water
points. Megamammal dung had nourished millions of insects, but after the extinction of
mammoths and mastodonts, some species of dung beetle disappeared (Stock 1972). Megamammals had carried large and small seeds in their guts and helped disperse numerous
plant taxa by passing the seeds in dung. After extinction, many species of plants changed
distribution in response to the loss of such dispersal vectors (Janzen and Martin 1982; also
see Barlow 2001; Dudley 1999). And megamammal carcasses and bones had fed numerous taxa of carnivorous predators and scavengers, including large mammalian species such
as dire wolf (extinct Canis dirus), avian species such as teratorn (extinct Teratornis merriami) and condors (extinct Gymnogyps amplus, extinct Breagyps clarki), and arthropods
such as blowy (extinct Protocrysomyia howardae) (Harris and Jefferson 1985; Stock
1972). After megamammal extinction, these species and others began dying out due to a
severe reduction in food supply.
Ongoing analyses of the extinct Pleistocene taxa (Stafford et al. 1997a, 1997b; Graham
et al. 1997) may soon indicate which genera disappeared Žrst from sampling locales, but
more dates are needed on well-preserved bones recovered in controlled contexts, and
much more stringent control of the laboratory processing is necessary to ensure that bone
chemistry is clearly known and lab pretreatments are comparable (Stafford 1988, 1999,
2000 pers. comm.). If it is ever shown that mammoths and mastodonts survived in North
America longer than the other large herbivores and carnivores, then the proposed ripple
effects of removing proboscideans will have to be rethought. But currently the radiometric data indicate that all of North America’s largest land mammals became extinct
very near 11,000 RCYBP. Human foragers in late Pleistocene North America hunted
mammoths and mastodonts, and this hunting led to the dying out for ever of those megamammals.
Acknowledgements
I am grateful to Paul Martin, Norman Owen-Smith and Janis Klimowicz for reading drafts
of this paper and suggesting improvements. I alone am responsible for shortcomings. The
Zimbabwe Department of National Parks and Wildlife Management has supported my
research on megamammal landscapes over the past twenty years, for which I am very
thankful. I also thank Adrian Lister for suggesting my name to Peter Rowley-Conwy,
editor of this collection of papers about eco-catastrophes.
Anthropology Department (096), University of Nevada, Reno
410
Gary Haynes
References
Adovasio, J. M., Pedler, D., Donahue, J. and Stuckenrath, R. 1999. No vestige of a beginning nor
prospect for an end: two decades of debate on Meadowcroft Rockshelter. In Ice Age People of North
America: Environments, Origins, and Adaptations (eds R. Bonnichsen and K. L. Turnmire).
Corvallis, OR: Oregon State University Press for the Center for the Study of the First Americans,
pp. 416–31.
Alroy, J. 1999. Putting North America’s end-Pleistocene megafaunal extinction in context: largescale analyses of spatial patterns, extinction rates, and size distributions. In Extinctions in Near
Time: Causes, Contexts, and Consequences (ed. R. D. E. MacPhee). New York: Kluwer
Academic/Plenum, pp. 105–43.
Alroy, J. 2000. An ecologically realistic simulation of North America’s end-Pleistocene megafaunal
mass extinction. Journal of Vertebrate Paleontology 20, Supplement 3: Abstracts of Papers, Sixtieth
Annual Meeting, Mexico City, 25–8 October, p. 26A.
Alvard, M. S. 1998. Evolutionary ecology and resource conservation. Evolutionary Anthropology,
7: 62–74.
Ammann, B., Birks, H. J. B., Brooks, S. J., Eicher, U., von Grafenstein, U., Hofmann, W., Lemdahl,
G., Schwander, J., Toboslki, K. and Wick, L. 2000. QuantiŽcation of biotic responses to rapid
climatic changes around the Younger Dryas: a synthesis. Palaeogeography, Palaeoclimatology,
Palaeoecology, 159(3–4): 3, 13–47.
Barlow, C. 2001. The Ghosts of Evolution: Nonsensical Fruits, Missing Partners, and Other EcoIogical Anachronisms. New York: Basic Books.
Barnes, R. F. W. and Jensen, K. L. 1987. How to Count Elephants in Forests. African Elephant and
Rhino Specialist Group Technical Bulletin Number 1.
Bell, R. H. V. 1971. A grazing ecosystem in the Serengeti. ScientiŽc American, 225: 86–93.
Bennett, K. D., Haberle, S. G. and Lumley, S. H. 2000. The Last Glacial-Holocene transition in
southern Chile. Science, 290: 325–8.
Bonnichsen, R. and Turnmire, K. L. (eds) 1991. Clovis: Origins and Adaptations. Corvallis, OR:
Oregon State University Press for the Center for the Study of the First Americans.
Brush, N. and Smith, F. 1994. The Martins Creek mastodon: a Paleoindian butchery site in Holmes
County, Ohio. Current Research in the Pleistocene, 1: 14–15.
Brush, N. and Yerkes, R. W. 1996. Microwear analysis of chipped stone tools from the Martins Creek
mastodon site, Holmes County, Ohio. Current Research in the Pleistocene, 13: 55–7.
Brush, N., Newman, M. and Smith, F. 1994. Immunological analysis of int akes from the Martins
Creek mastodon site. Current Research in the Pleistocene, 11: 16–18.
Catlin, G. (ed. P. Matthiessen) 1989[1844]. North American Indians (original title Letters and Notes
on the Manners, Customs and Conditions of the North American Indians Written During Eight Years’
Travel (1832–1839) Amongst the Wildest Tribes of Indians of North America). New York: Viking Press.
Charnov, E. L. 1976. Optimal foraging: the marginal value theorem. Theoretical Population Biology,
9: 129–36.
Clark, C. W. 1973. The economics of over-exploitation. Science, 181: 630–4.
De Boer, W. F., Ntumi, C. P., Correia, A. U. and Mafuca, J. M. 2000. Diet and distribution of
elephant in the Maputo Elephant Reserve, Mozambique. African Journal of Ecology, 38: 188–201.
Dent, R. J., Jr. 1995. Chesapeake Prehistory: Old Traditions, New Directions. New York: Plenum.
Dincauze, D. F. 1993. Fluted points in the eastern forests. In From Kostenki to Clovis: Upper Paleolithic – Paleo-Indian Adaptations (eds O. Soffer and N. D. Praslov). New York: Plenum, pp. 279–92.
Catastrophic extinction of mammoths and mastodonts
411
Dixon, E. J. 1993. Quest for the Origins of the First Americans. Albuquerque, NM: University of
New Mexico Press.
Dreimanis, A. 1967. Mastodons, their geological age and extinction in Ontario, Canada. Canadian
Journal of Earth Sciences, 4: 663–75.
Duckler, G. L. and van Valkenburgh, B. 1998. Exploring the health of late Pleistocene mammals:
the use of Harris lines. Journal of Vertebrate Paleontology, 18(1): 180–8.
Dudley, J. P. 1999. Seed dispersal of Acacia erioloba by African bush elephants in Hwange National
Park, Zimbabwe. African Journal of Ecology, 37(4): 375–85.
Duffy, K. 1984. Children of the Forest. New York: Dodd, Mead.
Eaton, S. B., Eaton, S. B. III and Konner, J. M. 1997. Paleolithic nutrition revisited: a twelve year
retrospective on its nature and implications. European Journal of Clinical Nutrition, 51: 207–16.
Edwards, S. W. 1992. Observations on the prehistory and ecology of grazing in California.
Fremontia, 20(1): 3–11.
Fiedel, S. J. 1999. Older than we thought: implications of corrected dates for Paleoindians. American
Antiquity, 64: 95–116.
Fiedel, S. J. 2000. The peopling of the New World: Present evidence, new theories and future directions. Journal of Archaeological Research, 8(1): 39–103.
Fisher, D. C. 1996. Extinction of proboscideans in North America. In The Proboscidea: Evolution
and Palaeoecology of Elephants and their Relatives (eds J. Shoshani and P. Tassy). Oxford: Oxford
University Press, pp. 296–315.
Fisher, J. W., Jr. 1987. Shadows in the forest: ethnoarchaeology among the Efe Pygmies. Doctoral
dissertation, Department of Anthropology, University of California, Berkeley.
Fisher, J. W., Jr. 1992. Observations of the late Pleistocene bone assemblage from the Lamb
Spring site, Colorado. In Ice Age Hunters of the Rockies (eds D. J. Stanford and J. S. Day).
Denver and Niwot, CO: Denver Museum of Natural History and University Press of Colorado,
pp. 51–82.
Giraldeau, L. A. 1997. The ecology of information use. In Behavioural Ecology: An Evolutionary
Approach, 4th edn (eds J. R. Krebs and N. B. Davis). Oxford: Blackwell, pp. 42–68.
Graham, R. W. and Lundelius, E. L. Jr. 1984. Coevolutionary disequilibrium and Pleistocene extinctions. In Quaternary Extinctions: A Prehistoric Revolution (eds P. S. Martin and R. G. Klein).
Tucson, AZ: University of Arizona Press, pp. 223–49.
Graham, R. W., Lundelius, E. L., Jr., Graham, M. A., Schroeder, E. K., Toomey, R. S. III, Anderson,
E., Barnosky, A. D., Burns, J. A., Churcher, C. S., Grayson, D. K., Guthrie, R. D., Harington, C.
R., Jefferson, G. T., Martin, L. D., McDonald, H. G., Morlan, R. E., Semken, H. A. Jr., Webb, S.
D., Werdelin, L. and Wilson, M. C. 1996. Spatial response of mammals to late Quaternary environmental uctuations. Science, 272: 1601–6.
Graham, R. W., Stafford, T. W. Jr. and Semken, H. A. Jr. 1997. Pleistocene extinctions: chronology,
non-analog communities, and environmental change. Paper presented at the American Museum of
Natural History, at the Center for Biodiversity and Conservation’s Spring Symposium, 17–18 April,
Humans and Other Catastrophes: Explaining Past Extinctions and the Extinction Process, New
York City.
Gramly, R. M. 1991. Blood residues upon tools from the East Wenatchee Clovis site, Douglas
County, Washington. Ohio Archaeologist, 41(4): 4–9.
Gramly, R. M. 1993. The Richey Clovis Cache: Earliest Americans aIong the Columbia River.
Buffalo, NY: Persimmon Press Monographs in Archaeology.
Guthrie, R. D. 1984. Mosaics, allelochemics and nutrients: an ecological theory of late Pleistocene
412
Gary Haynes
megafaunal extinctions. In Quaternary Extinctions (eds P. S. Martin and R. G. Klein). Tucson, AZ:
University of Arizona Press, pp. 259–98.
Hamilton, T. D. and Goebel, T. 1999. Late Pleistocene peopling of Alaska. In Ice Age Peoples of
North America: Environments, Origins, and Adaptations of the First Americans (eds R. Bonnichsen
and K. L. Turnmire). Corvallis, OR: Oregon State University Press for the Center for the Study of
the First Americans, pp. 156–99.
Harris, J. M. and Jefferson, G. T. (eds) 1985. Rancho La Brea: Treasures of the Tar Pits. NaturaI
History Museum of Los Angeles County Science Series 31.
Haynes, C. V., Jr. 1984. Stratigraphy and late Pleistocene extinction in the United States. In Quaternary Extinctions: A Prehistoric Revolution (eds P. S. Martin and R. G. Klein). Tucson, AZ:
University of Arizona Press, pp. 353–65.
Haynes, C. V., Jr. 1987. Clovis origin update. The Kiva, 52: 83–93.
Haynes, C. V., Jr. 1991. Geoarchaeological and paleohydrological evidence for a Clovis-age drought
in North America and its bearing on extinction. Quaternary Research, 35: 438–50.
Haynes, C. V., Jr. 1993. Clovis-Folsom geochronology and climatic change. In From Kostenki to
Clovis: Upper Paleolithic – Paleo-Indian Adaptations (eds O. Soffer and N. D. Praslov). New York:
Plenum, pp. 219–36.
Haynes, G. 1987. Where elephants die. NaturaI History, 96(6): 28–33.
Haynes, G. 1988. Longitudinal studies of African elephant death and bone deposits. Journal of
ArchaeologicaI Science, 15: 131–57.
Haynes, G. 1989. Late Pleistocene mammoth utilization in northeast Asia and North America.
Archaeozoologia, 3(1,2): 81–108.
Haynes, G. 1991. Mammoths, Mastodonts, and Elephants: Biology, Behavior, and the Fossil Record.
New York: Cambridge University Press.
Haynes, G. 1999. The role of mammoths in rapid Clovis dispersal. In Mammoths and the Mammoth
Fauna: Studies of an Extinct Ecosystem (eds G. Haynes, J. Klimowicz and J. W. F. Reumer). Deinsia,
6: 9–38.
Haynes, G. and Eiselt, B. S. 1999. The power of Pleistocene hunter-gatherers: forward and backward
searching for evidence about mammoth extinction. In Extinctions in Near Time: Causes, Contexts,
and Consequences (ed. R. D. E. MacPhee). New York: Kluwer Academic/Plenum, pp. 71–93.
Heinrich, B. 1991. Ravens in Winter. New York: Vintage Books.
Heinrich, B. 1999. Mind of the Raven: Investigations and Adventures with Wolf-Birds. New York:
Cliff Street Books.
Hester, J. J. 1972. Blackwater Locality No. 1: A StratiŽed, Early Man Site in Eastern New Mexico.
Fort Burgwin Research Center (Southern Methodist University) Publication No. 8.
Holliday, V. T. 1997. Paleoindian Geoarchaeology of the Southern High Plains. Austin, TX:
University of Texas Press.
Holliday, V. T. 2000. The evolution of Paleoindian geochronology and typology on the Great Plains.
Geoarchaeology, 15(3): 227–90.
Hoppe, K. A., Carlson, R. W. and Webb, S. D. 1999. Tracking mammoths and mastodons: reconstruction of migratory behavior using strontium isotope ratios. Geology, 27(5): 439–42.
Hyland, D. C., Tersak, J. M., Adovasio, J. M. and Siegel, M. I. 1990. IdentiŽcation of the species of
origin of residual blood on lithic material. American Antiquity, 55(1): 104–12.
Janzen, D. H. and Martin, P. S. 1982. Neotropical anachronisms: the fruits the gomphotheres ate.
Science, 215: 19–27.
Catastrophic extinction of mammoths and mastodonts
413
Jennings, J. D. 1989. Prehistory of North America, 3rd edn. Mountain View, CA: MayŽeld Publishing.
Johns, T., Mahunnah, R. L. A., Sanaya, P., Chapman, L. and Ticktin, T. 1999. Saponins and phenolic
content in plant dietary additives of a traditional subsistence community, the Batemi of Ngorongoro District, Tanzania. Journal of Ethnopharmacology, 66: 1–10.
Johns, T., Nagarajan, M., Parkipuny, M. L. and Jones, P. J. H. 2000. Maasai gummivory: implications
for paleolithic diets and contemporary health. Current Anthropology, 41(3): 453–9.
Kay, C. E. 1994. Aboriginal overkill: the role of Native Americans in structuring western ecosystems. Human Nature, 5(4): 359–98.
Kay, C. E. 1995. Aboriginal overkill and native burning: implications for modern ecosystem
management. Western Journal of Applied Forestry, 10(4): 120–6.
Kelly, R. C. and Todd, L. C. 1988. Coming into the country: early Paleoindian hunting and mobility.
American Antiquity, 53: 231–44.
King, J. E. and Saunders, J. J. 1984. Environmental insularity and the extinction of the American
mastodont. In Quaternary Extinctions: A Prehistoric Revolution (eds P. S. Martin and R. G. Klein).
Tucson, AZ: University of Arizona Press, pp. 315–44.
Koch, P. L., Hoppe, K. A. and Webb, S. D. 1998. The isotopic ecology of late Pleistocene mammals
in North America – Part 1. Florida. Chemical Geology, 152(1–2): 119–38.
Kooyman, B., Tolman, S., Hills, L. V. and McNeil, P. 2000. The archaeological context of late Pleistocene remains from the Wally’s Beach site, Alberta. Paper presented at the 65th Annual Meeting of
the Society for American Archaeology. Society for American Archaeology Abstracts of the 65th
Annual Meeting, 5–9 April Philadelphia, PA.
Krech, S., III. 1999. The Ecological Indian: Myth and History. New York: Norton.
Laub, R. S. 1994. The Pleistocene/Holocene transition in western New York state: fruits of interdisciplinary studies at the Hiscock site. In Great Lakes ArchaeoIogy and Paleoecology: ExpIoring
Interdisciplinary Initiatives for the Nineties (ed. R. I. MacDonald). Waterloo, Ontario: The Quaternary Sciences Institute, University of Waterloo, pp. 155–67.
Laub, R. S. and Haynes, G. 1998. Fluted points, mastodons, and evidence of late-Pleistocene
drought at the Hiscock site, western New York state. Current Research in the Pleistocene, 15: 32–4.
Laub, R. S., Miller, N. G. and Steadman, D. W. (eds) 1988. Late Pleistocene and Early Holocene
Paleoecology and Archeology of the Eastern Great Lakes Region. BuIletin of the Buffalo Society of
Natural Sciences 33.
Laub, R. S., Dufort, C. A. and Christenson, D. J. 1994. Possible mastodon gastrointestinal and fecal
contents from the late Pleistocene of the Hiscock site, western New York state. In Studies in Stratigraphy and Paleontology in Honor of Donald W. Fisher (ed. E. Landing). New York State Museum
Bulletin 481, pp. 135–48.
Laws, R. M., Parker, I. S. C. and Johnstone, R. C. B. 1975. Elephants and Their Habitats: The
Ecology of Elephants in North Bunyoro, Uganda. Oxford: Clarendon Press.
Lee, R. B. 1968. What hunters do for a living, or, how to make out on scarce resources. In Man the
Hunter (eds R. B. Lee and I. DeVore). Chicago: Aldine, pp. 30–48.
Lincoln, R. J. and Boxshall, G. A. 1987. The Cambridge Illustrated Dictionary of Natural History.
Cambridge: Cambridge University Press.
Loy, T. H. and Dixon, E. J. 1998. Blood residues on uted points from eastern Beringia. American
Antiquity, 63: 21–46.
McAvoy, J. M. and McAvoy, L. D. 1997. Archaeological Investigations of Site 44SX202, Cactus Hill,
Sussex County, Virginia. Virginia Department of Historic Resources, Research Report Series No.
8.
414
Gary Haynes
MacDonald, G. F. 1968. Debert: A Palaeo-Indian Site in Central Nova Scotia. National Museums of
Canada Anthropology Papers No. 16.
Martin, P. S. 1967. Prehistoric overkill. In Pleistocene Extinctions: The Search for a Cause (eds P. S.
Martin and H. E. Wright). New Haven, CT: Yale University Press, pp. 75–120.
Martin, P. S. 1982. The pattern and meaning of Holarctic mammoth extinction. In Paleoecology of
Beringia (eds D. M. Hopkins, J. V. Mathews, C. E. Schweger and S. B. Young). New York: Academic
Press, pp. 399–408.
Martin, P. S. 1984. Prehistoric overkill: the global model. In Quaternary Extinctions: A Prehistoric
Revolution (eds P. S. Martin and R. G. Klein). Tucson, AZ: University of Arizona Press, pp.
354–403.
Martin, P. S. 1990. 40,000 years of extinctions on the ‘planet of doom’. Palaeogeography, Palaeoclimatology, Palaeoecology, 82: 187–201.
Martin, P. S. and Klein, R. G. (eds) 1984. Quaternary Extinctions: A Prehistoric Revolution. Tucson,
AZ: University of Arizona Press.
Martin, P. S. and Steadman, D. W. 1999. Prehistoric extinctions on islands and continents. In Extinctions in Near Time: Causes, Contexts, and Consequences (ed. R. D. E. MacPhee). New York: Kluwer
Academic/Plenum, pp. 17–55.
Martin, P. S. and Stuart, A. J. 1995. Mammoth extinction: two continents and Wrangel Island. Radiocarbon, 37(1): 7–10.
Meltzer, D. J. 1988. Late Pleistocene human adaptations in Eastern North America. Journal of
World Prehistory, 2: 1–53.
Meltzer, D. J. 1993. Is there a Clovis adaptation? In From Kostenki to Clovis: Upper Paleolithic –
Paleo-Indian Adaptations (eds O. Soffer and N. D. Praslov). New York: Plenum, pp. 293–310.
Meltzer, D. J. and Smith B. D. 1986. Paleoindian and Early Archaic subsistence strategies in eastern
North America. In Foraging, Collecting and Harvesting: Archaic Period Subsistence and Settlement
in the Eastern Woodlands (ed. S. W. Neusius). Center for Archaeological Investigations Occasional
Paper 6. Carbondale: Southern Illinois University, pp. 3–31.
Mithen, S. 1993. Simulating mammoth hunting and extinction: implications for the late Pleistocene
of the central Russian Plain. In Hunting and Animal Exploitation in the Later Palaeolithic and
Mesolithic of Eurasia (eds G. L. Peterkin, H. M. Bricker and P. Mellars). Anthropological Papers
of the American Anthropological Association, Number 4, pp. 163–78.
Molyneaux, B. L. 2000. Update on the Northern Loess Hills Clovis Point. Newsletter of the Iowa
Archaeological Society, 50(4): 1–2
Owen-Smith, R. N. 1982. Dispersal and the dynamics of large herbivores in enclosed areas: implications for management. In Management of Large Mammals in African Conservation Areas (ed. R.
N. Owen-Smith). Pretoria: HAUM Educational Publishers, pp. 127–40.
Owen-Smith, R. N. 1987. Pleistocene extinctions: the pivotal role of megaherbivores. Paleobiology,
13: 351–62.
Owen-Smith, R. N. 1988. Megaherbivores: The Inuence of Very Large Body Size on Ecology.
Cambridge: Cambridge University Press.
Owen-Smith, R. N. 1999. The interaction of humans, megaherbivores, and habitats in the late
Pleistocene extinction event. In Extinctions in Near Time: Causes, Contexts, and Consequences (ed.
R. D. E. MacPhee). New York, Kluwer Academic/Plenum, pp. 57–69.
Putschkov, P. V. 1997. Were the mammoths killed by the warming? Testing the climatic versions of
Würm extinctions. Vestnik Zoologii (Journal of the Schmalhausen lnstitute of Zoology, National
Academy of Sciences, Ukraine).
Catastrophic extinction of mammoths and mastodonts
415
Rachlow, J. L. 1997. Demography, behavior, and conservation of white rhinos. Doctoral dissertation, Program in Evolution, Ecology, and Conservation Biology, University of Nevada, Reno.
Rachlow, J. L., Berkeley, E. V. and Berger, J. 1998. Correlates of male mating strategies in white
rhinos (Ceratotherium simum). Journal of Mammalogy, 79: 1317–24.
Richards, M. P., Hedges, R. E. M., Jacobi, R., Current, A. and Stringer, C. 2000. FOCUS: Gough’s
Cave and Sun Hole Cave human stable isotope values indicate a high animal protein diet in the
British Upper Palaeolithic. Journal of ArchaeologicaI Science, 27: 1–3.
Rodbell, D. T. 2000. The Younger Dryas: cold, cold everywhere? Science, 290: 285–6.
Rutter, N. W., Weaver, A. J., Rokosh, D., Fanning, A. F. and Wright, D. G. 2000. Data-model
comparison of the Younger Dryas event. Canadian Journal of Earth Sciences, 37: 811–30.
Sealy, J. and Pfeiffer, S. 2000. Diet, body size, and landscape use among Holocene people in the
southern Cape, South Africa. Current Anthropology, 41(4): 642–55.
Sikes, S. K. 1971. The Natural History of the African Elephant. New York: American Elsevier.
Smith, E. A. and Wishnie, M. 2000. Conservation and subsistence in small-scale societies. Annual
Review of Anthropology, 29: 493–524.
Speth, J. D. and Spielmann, K. 1983. Energy source, protein metabolism, and hunter-gatherer
subsistence strategies. Journal of Anthropological Archaeology, 2: 1–31.
Spiess, A. and Wilson D. B. 1987. Michaud: A Paleoindian Site in the New England-Maritimes
Region. Maine Archaeological Society Occasional Publications in Maine Archaeology 6.
Stafford, T. W., Jr. 1988. Accelerator 14C dating of late Pleistocene megafauna. Current Research
in the Pleistocene, 5: 41–3.
Stafford, T. W., Jr. 1999. Chronologies for the oldest human skeletons in the New World. Geological
Society of America, 31(7)(Annual Meeting, Abstracts with Program): 24.
Stafford, T. W., Jr., Jull, A. J. T., Brendel, K., Duhamel, R. C. and Donahue, D. 1987. Study of bone
radiocarbon dating accuracy at the University of Arizona NSF Accelerator Facility for Radioisotope Analysis. Radiocarbon, 29(1): 24–44.
Stafford, T. W., Jr., Brendel, K. and Duhamel, R. C. 1988. Radiocarbon, 13C and 15N analysis of
fossil bone: removal of humates with XAD-2 resin. Geochimica et Cosmochimica Acta, 52: 2257–67.
Stafford, T. W., Jr., Graham, R. W., Semken, H. A., Jr. and Southon, J. 1997a. AMS 14C chronologies for late Pleistocene mammal extinctions and human migrations in North America. Abstracts
of 1997 CAVEPS (on-line: <http: //bioscience.babs.unsw.edu.au/CAVE T.htm>), University of New
South Wales.
Stafford, T. W., Jr., Graham, R. W., Semken, H. A., Jr. and Southon, J. 1997b. Chronology and
timing of the terminal Pleistocene extinction event in the mid-latitudes of North America. Paper
presented at 7th International Theriological Congress, Acapulco, Mexico.
Stock, C. 1972. Rancho La Brea: A Record of Pleistocene Life in California, 6th edn. Los Angeles
County Museum of Natural History Science Series No. 20, Paleontology, No. 11.
Stone, R. 1998. A bold plan to re-create a long-lost Siberian ecosystem. Science, 282: 31–4.
Stuart, A. J. 1991. Mammalian extinctions in the late Pleistocene of northern Eurasia and North
America. Biological Reviews, 66: 453–562.
Stuart, A. J. 1999. Late Pleistocene megafaunal extinctions: a European perspective. In Extinctions
in Near Time: Causes, Contexts, and Consequences (ed. R. D. E. MacPhee). New York: Kluwer
Academic/Plenum, pp. 257–69.
Sullivan, R. 2000. A Whale Hunt. New York: Scribner.
416
Gary Haynes
Taylor, R. E., Haynes, C. V., Jr. and Stuiver, M. 1996. Clovis and Folsom age estimates: stratigraphic
context and radiocarbon calibration. Antiquity, 70(269): 515–25.
Theuerkauf, J. and Ellenberg, H. 2000. Movements and defaecation of forest elephants in the moist
semi-deciduous Bossematié Forest Reserve, Ivory Coast. African Journal of Ecology, 38(3): 258–61.
Webster, D. and Webster, G. 1984. Optimal hunting and Pleistocene extinction. Human Ecology,
12: 275–89.
Western, D. 1989. The ecological value of elephants: a keystone role in African ecosystems. In The
Ivory Trade and the Future of the African Elephant, Vol. 2, Section 5.2 (co-ordinator S. Cobb).
Oxford: The Ivory Trade Review Group.
Western, D. 1991. When the forest falls silent. In Elephants: The Deciding Decade (ed. R.
Orenstein). Toronto, Ontario: Key Porter, pp. 83–95.
Willey, G. R. 1966. An Introduction to American Archaeology, Vol. 1, North and Middle America.
Englewood Cliffs, NJ: Prentice-Hall.
Winterhalder, B. 1981. Optimal foraging strategies and hunter-gatherer research in anthropology:
theory and models. In Hunter-Gatherer Foraging Strategies: Ethnographic and Archaeological
Analyses (eds B. Winterhalder and E. A. Smith). Chicago: University of Chicago Press, pp. 13–35.
Yesner, D. R. 1980. Maritime hunter-gatherers: ecology and prehistory. Current Anthropology, 21:
727–50.
Zimov, S. A., Chuprynin, V. I., Oreshko, A. P., Chapin, F. S. III, Reynolds, J. F. and Chapin, M. C.
1995. Steppe-tundra transition: a herbivore-driven biome shift at the end of the Pleistocene.
American Naturalist, 146: 765–94.