From: PO4::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 12-APR-1996 01:53:24.46 To: Multiple recipients of list QUATERNARY CC: Subj: Re: pleistocene extinctions; buffalo David k-yamaguchi wrote: > > hi quaternites: > > i have two basic questions that listserv members can probably help me > with: > > 1) is there a recent review paper updating paul martin's n. american > megafauna pleistocene extinctions work? what is the current > consensus? caused by overkill by humans? climatic change? a > combination of the two factors? > > 2) why did buffalo survive? > > any help appreciated, > > stumped in sapporo, > dave yamaguchi > davidoi@ffpri-hkd.affrc.go.jp Dave: I'm afraid I have the tendancy to view it as being the combination; however, the environmental change factor is probably the most important. It's easy to forget the extensive degree of change that occurred with the end of the Pleistocene. The actual effects were felt not only in glaciated areas, but throughout much of the unglaciated continent. When you consider the potential for megafauna, as well as other species, to fail to adapt to the changes in the ecosystem, it isn't really that hard to appreciate large scale extinction. Throw in a reasonably new predator into the ecosystem and there is plenty of impetus to push some species over the brink. -- Douglas Rutherford ycruther@yknet.yk.ca Yukon College, Academic Studies/Professional Studies Whitehorse, YT, Canada Tel. (403) 668-8809 From: PO2::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 12-APR-1996 06:31:15.84 To: Multiple recipients of list QUATERNARY CC: Subj: Re: pleistocene extinctions; buffalo To Dave Rutherford's response, I would add only that there were also major extinctions among smaller critters as well, though they tend to be overlooked and are less well-known. Donald Grayson documented the demise of some twenty-odd major groups of small birds as well back in a paper published in SCIENCE back in the 1970s. Many of these were no larger than sparrows, which (a) would hardly have been the target of any hunting, and (b) likely would have survived happily if they were. Consider the problems people have encountered in trying to eradicate European rock doves and starlings in North America! - Bob Nelson *********************************************** Robert E. Nelson, Chair Phone: [207] 872-3247 Department of Geology FAX: [207] 872-3555 Colby College e-mail: renelson@colby.edu 5804 Mayflower Hill Drive Waterville, Maine 04901-8858 "Good science consists mostly of play disguised as work." - E. O. Wilson *********************************************** >hi quaternites: > >i have two basic questions that listserv members can probably help me >with: > >1) is there a recent review paper updating paul martin's n. american > megafauna pleistocene extinctions work? what is the current > consensus? caused by overkill by humans? climatic change? a > combination of the two factors? > >2) why did buffalo survive? > >any help appreciated, > >stumped in sapporo, >dave yamaguchi >davidoi@ffpri-hkd.affrc.go.jp From: PO3::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 12-APR-1996 09:24:55.82 To: Multiple recipients of list QUATERNARY CC: Subj: Re: pleistocene extinctions; buffalo dave yamaguchi asks >1) is there a recent review paper updating paul martin's n. american > megafauna pleistocene extinctions work? what is the current > consensus? caused by overkill by humans? climatic change? a > combination of the two factors? > >2) why did buffalo survive? The answer to this question certainly depends on what the latest paper's you are looking at. The following are some relatively recent (last 12 years) papers that summarize some of the arguments. I would say that the most recent comprehensive review is P.S. Martin and R.G. Klein (eds.), _Quaternary Extinctions: A Prehistoric Revolution_, Tucson, AZ: University of Arizona Press, 892pp. (contains a very good set of papers that discuss various aspects of the debate. It is now about 12 years old, but most of the discussions remain current.) Another interesting paper that is of about the same vintage would be the following: R.D. Guthrie, 1984, Alaskan Megabucks, Megabulls and Megarams: the issue of Pleistocene gigantism, IN (H.H. Genoways and M.R. Dawson, eds.) _Contributibutions in Quaternary Vertebrate Paleontology: A Volume in Memorial to John E. Guilday, Carnegie Museum of Natural History, Special Publication_, 8: 482-510. Moving somewhat more recently see E.L. Lundelius, Jr., 1989, The implications of disharmonius assemblages for Pleistocene extinctions, _Journal of Archaeological Science_, 16: 407-417. Guthrie deals further with some of his ideas in the following: R.D. Guthrie, 1990, _Frozen Fauna of the Mammoth Steppe: The Story of Blue Babe_, Chicago, IL: University of Chicago Press, 323pp. (This book is a must read for people interested in Quaternary Mammals and especially bison.) You might also look at L.D. Agenbroad, J.I. Mead, and L.W. Nelson, 1990, _Megafauna and Man: Discovery of America's Heartland, The Mammoth Site of Hot Springs, South Dakota, Inc. Scientific Papers, V. 1._ Hot Springs, SD and Flagstaff, AZ: co-published by the The Mammoth Site of Hot Springs, South Dakota, Inc. and Northern Arizona University. 143pp. (This is a volume based on a 1989 symposium and contains papers on possible Late Pleistocene extinction causes by R.D. Guthrie, R. W. Graham, P.S. Martin and T.W. Stafford, Jr. Several other papers also provide helpful perspectives.) Continuing more recently see D.K. Grayson, 1991, Late Pleistocene mammalian extinctions in the in North America: taxonomy, chronology, and explanations, _Journal of World Prehistory, 5: 193-231. and A.J. Stuart, 1991, Mammalian extinctions in the late Pleistocene of northern Eurasia and North America, _Biological Reviews_, 66: 453-562. The papers and books listed above are just some of the better reviews of aspects of the debate. (Actually, I'm a little surprised that I can't come up with anything in the 1993 range off-hand.) There are many other good discussions of the subject. Some of the names to look for include L.D. Agenbroad, R. W. Graham, R.D. Guthrie, D. K. Grayson, E.L. Lundelius, Jr., L.D. Martin, P.S. Martin, J.I. Mead, T.W. Stafford, Jr., D.W. Steadman (mainly birds), S.D. Webb. (there are many others as well, I appologize to those I have missed). and lastly, a recent publication has gathered much of the data together into a usable database. Faunmap Working Group, 1994, FAUNMAP: A Database Documenting Late Quaternary Distributions of Mammal Species in the United States, Illinois State Museum, Scientific Papers, 25: 690pp. (This volume discusses the database which contains the mammalian fauna, dates, depositional informations, etc from almost 3000 Late Plesitocene and Holocene sites from the 48 contiguous United States. More information on the database (including online querying is available on the ISM WWW site at the following URL: http://www.museum.state.il.us/research/faunmap/ . The FAUNMAP project is directed by R.W. Graham and E.L. Lundelius, Jr.) [ note depending on how fast this note gets distributed -- the ISM WWW site will be down for upgrading for several hours starting 10 AM (cental daylight time, 1500 Greenwich) April 12, 1996 ] Hope these references help. I would say that the current consensus on the extinction (at least among Quaternary mammal paleontologists) is that the extinction was primarily driven by environmental change. However, the consensus may be different if you talk to other groups (like archaeologists). Rick ------------------------------------------------------------------- Rickard S. Toomey, III toomey@museum.state.il.us Illinois State Museum - RCC, 1011 E. Ash St., Springfield, IL 62703 phone (217) 524-7908 fax (217) 785-2857 Illinois State Museum Homepage URL http://www.museum.state.il.us/ From: PO4::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 12-APR-1996 10:54:35.05 To: Multiple recipients of list QUATERNARY CC: Subj: Re: pleistocene extinctions; buffalo Dave, Ummm, define "updating" (1) Here's a bibliography Haynes, C.V. 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 35:438-450. Markgraf, V. 1985. Late Pleistocene faunal extinctions in southern Patagonia. Science 228:1110-1112 Martin, P.S. 1966. Africa and Pleistocene overkill. Nature 212:339-342. Martin, P.S. 1967. Prehistoric overkill. in Martin and Wright Martin, P.S. 1967. Pleistocene overkill. Natural History 76:32-38. Martin, P.S. 1973. The discovery of America. Science 179:969-974. Martin, P.S. and Klein, R.G. 1984. Quaternary Extinctions a prehistoric revolution. Univ. Arizona Press, Tucson. Martin, P.S. and Wright, H.E., Jr. 1967. Pleistocene extinctions, the search for a cause. Yale Univ. Press, New Haven. (2) why did buffalo survive? A. why not? So far, there has not been an extinction where *NOTHING* survived. Owen. Owen K. Davis, Professor 520 621-7953 Department of Geosciences FAX 621-2672 University of Arizona palynolo@geo.arizona.edu Tucson, Arizona 85721 http://geo.arizona.edu/palynology From: PO2::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 12-APR-1996 13:52:41.00 To: Multiple recipients of list QUATERNARY CC: Subj: Re: pleistocene extinctions; buffalo I agree that the extinctions are due to a combination of causes. But, I don't think it is adequate to leave it at that. I invite you to follow the clews, along with the famous scientific investigator Skylark Holmes and Dr. Janet Watson, in a mystery story which presents the case, from the literature, on how the introduction of H. sapiens and ecological change might have combined. The mystery story is available on my home page. I haven't gotten the bibliography up yet but expect to before May. Here's the URL- http://www.well.com/user/elin/mstry.htm In the mystery story I suggest that second order predation (H. sapiens hunting predators) unstuck the ecological balance and caused a boom and then bust of herbivore populations. I did a more formal presentation of it at last year's CANQUA meeting. I have been working on a computer simulation of the boom /bust theory and I will be presenting current at the CAG/CANQUA meeting in Saskatoon, CA and will have a poster at AMQUA in Flagstaff, AZ both this May. If you are going to be at either come and play with the model. (the abstract is below) In answer to your bison question -- If there was a boom /bust in herbivore populations then there would be an extremely competitive situation. Ruminants, as opposed to cecal digesters, (like horses and elephants) would be selectively favored, as would smaller animals, or the smaller individuals in populations of animals because they could reproduce the fasteset using the least resources. Abstract: Climate change theories put forward to explain the extinctions at the close of the Pleistocene are unsatisfactory because the animals in question survived changes of similar magnitude. The overkill theory is unsatisfactory because predators cannot hunt their prey to extinction without starving themselves. Combining the theories, without a proposed mechanism, is incomplete and inadequate. All current models assume animal populations decrease monotonically to extinction. An alternate scenario and computer simulation characterized by a boom/bust population pattern is presented. It suggests: H. sapiens reduced predator populations, causing a herbivore population boom, leading to overgrazing of trees as well as grass, resulting in environmental exhaustion and extinction of herbivores. If true, increased continentality of the Holocene may be accounted for thus: herbivore population explosion forces animals to eat all available food, browsers and mixed feeders denude the mixed grassland/woodland of trees, the changed vegetation pattern reduces atmospheric moisture from transpiration resulting in increased continentality. An interactive system dynamics computer simulation will be available for demonstration and testing. elin Elin Whitney-Smith elin@tmn.com http://www.well.com/user/elin >hi quaternites: > >i have two basic questions that listserv members can probably help me >with: > >1) is there a recent review paper updating paul martin's n. american > megafauna pleistocene extinctions work? what is the current > consensus? caused by overkill by humans? climatic change? a > combination of the two factors? > >2) why did buffalo survive? > >any help appreciated, > >stumped in sapporo, >dave yamaguchi >davidoi@ffpri-hkd.affrc.go.jp > > From: PO3::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 13-APR-1996 11:18:02.84 To: Multiple recipients of list QUATERNARY CC: Subj: Re: pleistocene extinctions; buffalo This is surely a hot topic, to judge from the response! None addresses the possibility of a catastrophic cause, however. Is Lyellian uniformitarianism universal among listees, or are the catastrophists just reticent? I recommend a book named "WHEN THE EARTH NEARLY DIED" by two British geoscientists, D.S. Allan and J.B. Delair, Gateway Books, Bath (ISBN: 1 85860 008 1) for a scholarly analysis of the worldwide data indicative of a sudden, earth-shaking event at about 11,500 ybp. In the process the authors reinterpret the Pleistocene/Holocene transition and make a significant contribution to science with a much better statement of an old theory than I have seen before. I have to disagree with a some of the detail, but find the comprehensiveness of coverage and overall soundness of argument exceptional and convincing. My argument against such simple mechanisms as climate change and human predation is that they fail to account for the parallel geological evidence, i.e. they are poor science. Has anyone else on the list read the book? His/her thoughts?? C. Warren Hunt, P. Geol. archeanc@freenet/calgary/ab/ca From: PO3::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 13-APR-1996 11:31:43.88 To: Multiple recipients of list QUATERNARY CC: Subj: Re: pleistocene extinctions; buffalo Predation fails to account for the temporally associated geological features of catastrophic nature associated with the Pleistocene/Holocene transition. You would find a lot of food for thought in the book "WHEN THE EARTH NEARLY DIED" by D.S. Allan and J.B. Delair, Gateway Books, (ISBN: 1 85860 008 1) 1995. This is a scholarly compilation of worldwide geological, paleontological, anthropological, and astronomical data with a conclusion that I find convincing. The book is highly readable; and I find only a few local geological facts with which I can take exception. C. Warren Hunt, P. Geol. archeanc@freenet.calgary.ab.ca From: PO4::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 13-APR-1996 14:17:23.47 To: Multiple recipients of list QUATERNARY CC: Subj: Re: pleistocene extinctions; buffalo Hallo, I have not read much about vertebrate extinctions across the Weichselian/Holocene transition. Therefore I do not know much about arguments of various people and their theories. My points are the following. - Are the extinctions only in large herbivore mammals ? I don't know of extinctions among smaller and other organisms like invertebrates. There are for instance, at least in Europe, no extinctions among molluscs. What make large herbivore mammals special ? - As far as I know, but I might be wrong, no similar extinctions at such a scale have been observed across earlier glacial/interglacial boundaries. Why not ? What makes the Weichselian/Holocene transition special ? Although I am convinced that each "climatic cycle" has its own unique characters, I can not believe that climate and ecological factors are the main triggers. Similar circumstances must have occurred during each transition. Therefore another cause must have been present. Something that was not present during other transitions, call it therefore "catastrophic". If not man, what else, and when exactly ? Tom ------------------------------------------------------------------------------ Tom Meijer e-mail: T.Meijer@Inter.NL.net & T.Meijer@RGD.NL ------------------------------------------------------------------------------ Political decisions are made by expertologists with a thin twodimensional brainframe (This estimate of dimensional complexity may be wildly optimistic). ------------------------------------------------------------------------------ From: PO3::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 15-APR-1996 13:51:02.99 To: Multiple recipients of list QUATERNARY CC: Subj: PLEISTOCENE EXTINCTIONS I'm glad this enjoyable donnybrook is still in progress. Here's a contribution: - Am I correct in believing that nobody has yet suggested epidemic disease among the big ungulates as a cause of their extinction, followed by starvation of the carnivores? Some diseases attack several host species. Diseases could have been brought in via Beringia and attacked populations with no natural immunity to them. Bison, having originated in Eurasia, might have had immunity. The opinions of veterinarians shd be sought. - In my 1991 semipopular book AFTER THE ICE AGE: THE RETURN OF LIFE TO GLACIATED NORTH AMERICA, I suggested that a catastrophe of one sort or another was the only poss explanation, tho' I made no surmises about what kind of catastrophe. A succession of big epidemics would BE a catastrophe. The idea of epidemic(s) occurred to me since writing the book. P.S. Martin's arguments that Eurasian immigrants were immune to hunting pressure but that indigenous American spp were not applies equally to disease immunity. I listed the extinct/extant spp by region of origin on p. 256 of my book. - Thanks for the ref to the Allan & Delair book. - Why this search for a "consensus"? What have consensuses to do with science? Chris Pielou E. C. Pielou, RR #1, Denman Island B.C. CANADA V0R 1T0 From: PO3::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 15-APR-1996 15:11:40.98 To: Multiple recipients of list QUATERNARY CC: Subj: Re: PLEISTOCENE EXTINCTIONS The disease concept is powerful for the animal world, but, as I said, there are so many specifically geological clues to catastrophe that there must have been environmental chaos of immense consequences. Allan & Delair give that a great boost with their thoroughness. But I still see a need for more than the one great catastrophe that they advocate. I will be tuned for more on this intriguing subject! C. Warren Hunt On Mon, 15 Apr 1996, E.C.Pielou wrote: > I'm glad this enjoyable donnybrook is still in progress. Here's a contribution: > > - Am I correct in believing that nobody has yet suggested epidemic disease > among the big ungulates as a cause of their extinction, followed by > starvation of the carnivores? Some diseases attack several host species. > Diseases could have been brought in via Beringia and attacked populations > with no natural immunity to them. Bison, having originated in Eurasia, > might have had immunity. The opinions of veterinarians shd be sought. > > - In my 1991 semipopular book AFTER THE ICE AGE: THE RETURN OF LIFE TO > GLACIATED NORTH AMERICA, I suggested that a catastrophe of one sort or > another was the only poss explanation, tho' I made no surmises about what > kind of catastrophe. A succession of big epidemics would BE a catastrophe. > The idea of epidemic(s) occurred to me since writing the book. P.S. > Martin's arguments that Eurasian immigrants were immune to hunting pressure > but that indigenous American spp were not applies equally to disease > immunity. I listed the extinct/extant spp by region of origin on p. 256 of > my book. > > - Thanks for the ref to the Allan & Delair book. > > - Why this search for a "consensus"? What have consensuses to do with science? > > Chris Pielou > > E. C. Pielou, > RR #1, > Denman Island > B.C. CANADA V0R 1T0 > From: PO3::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 15-APR-1996 15:35:15.66 To: Multiple recipients of list QUATERNARY CC: Subj: Re: PLEISTOCENE EXTINCTIONS Chris Pielou brought up the issue of epidemic disease as a cause of the terminal Pleistocene megafaunal extinction; Ross MacPhee of the American Museum of Natural History published a lengthy exposition of such a hypothesis ( under the moniker 'Hyperdisease') last year. He can no doubt provide the full reference. *************************** Donald A. McFarlane Joint Science Department, The Claremont Colleges 925 N. Mills Ave., Claremont CA 91711 Tel: (909) 607-2564 Fax: (909) 621 -8588 *************************** From: PO3::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 16-APR-1996 06:04:38.31 To: Multiple recipients of list QUATERNARY CC: Subj: Re: PLEISTOCENE EXTINCTIONS I think that epidemics are a most unlikely expalnation for continent wide extinctions. An extinction of this type is the same sort of event in evolutionary terms as the megaherbiovres undergoing popluation expansion, eating all the grass and starving themselves to extinction. Who would credit such a scenario? Biological systems rarely run like this, the componens of these systems adapt either genotypically in the evolutionary sense or in the immediate ontogenetic sense. As pathogens probably have a greater potential for evolutionary change than their hosts it is the 'experience' of the pathogens that counts in the long run not the immunological naivity of the large animal populations. Whilst super-virulent pathogens can cause local catastrophe, they tend to evolve towards intermediate levels of pathogenicity in the medium term as this maximises their reproductive success. Even when pathogens such as myxamatosis are deliberately selected for virulence and then introduced to a naive wild population, extinction only occurs locally with the pathogen rapidly evolving towards lowered virulence as it squeezes through population bottlenecks. The myth of the exterminator pathogen is just that. Consider the evolutionary achievements of viruses with different levels of virulence AIDS vs Ebola. AIDS is not a wipeout virus it has propagated itself widely. Ebola never gets going in the human population as it kills all the hosts before enough transmissions take place to achieve any growth. The disease model just doesn't wash for the whole continent. Mark Leney Department of Biological Anthropology University of Cambridge mdl1002@cus.cam.ac.uk From: PO4::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 16-APR-1996 09:45:58.11 To: Multiple recipients of list QUATERNARY CC: Subj: Re: PLEISTOCENE EXTINCTIONS I'd suggest that if the cause was disease the animials who had the disease were the predators rather than the herbivores. If predator populations were reduced herbivore populations would boom, overgraze then bust and we would have the pattern of extinctions we now see (ruminants and smaller types). I have suggested that H. sapiens hunting further up on the food chain would have a similar impact. I will be presenting a computer simulation of same at CANQUA and will have a poster at AMQUA - Check out the mystery of the Arboricidal megaherbivores at: http://www.well.com/user/elin/mstry.htm elin elin@tmn.com http://www.well.com/user/elin On Mon, 15 Apr 1996, E.C.Pielou wrote: > I'm glad this enjoyable donnybrook is still in progress. Here's a contribution: > > - Am I correct in believing that nobody has yet suggested epidemic disease > among the big ungulates as a cause of their extinction, followed by > starvation of the carnivores? Some diseases attack several host species. > Diseases could have been brought in via Beringia and attacked populations > with no natural immunity to them. Bison, having originated in Eurasia, > might have had immunity. The opinions of veterinarians shd be sought. > > - In my 1991 semipopular book AFTER THE ICE AGE: THE RETURN OF LIFE TO > GLACIATED NORTH AMERICA, I suggested that a catastrophe of one sort or > another was the only poss explanation, tho' I made no surmises about what > kind of catastrophe. A succession of big epidemics would BE a catastrophe. > The idea of epidemic(s) occurred to me since writing the book. P.S. > Martin's arguments that Eurasian immigrants were immune to hunting pressure > but that indigenous American spp were not applies equally to disease > immunity. I listed the extinct/extant spp by region of origin on p. 256 of > my book. > > - Thanks for the ref to the Allan & Delair book. > > - Why this search for a "consensus"? What have consensuses to do with science? > > Chris Pielou > > E. C. Pielou, > RR #1, > Denman Island > B.C. CANADA V0R 1T0 > From: PO3::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 16-APR-1996 09:51:34.68 To: Multiple recipients of list QUATERNARY CC: Subj: Re: PLEISTOCENE EXTINCTIONS On Tue, 16 Apr 1996, Mark Leney wrote: > I think that epidemics are a most unlikely expalnation for continent wide > extinctions. An extinction of this type is the same sort of event in > evolutionary terms as the megaherbiovres undergoing popluation > expansion, eating all the grass and starving themselves to extinction. > Who would credit such a scenario? Biological systems rarely run like > this, the componens of these systems adapt either genotypically in the Or perhaps we only tend to find those that do not. > evolutionary sense or in the immediate ontogenetic sense. As pathogens > probably have a greater potential for evolutionary change than their > hosts it is the 'experience' of the pathogens that counts in the long run > not the immunological naivity of the large animal populations. Whilst > super-virulent pathogens can cause local catastrophe, they tend to evolve > towards intermediate levels of pathogenicity in the medium term as this > maximises their reproductive success. Even when pathogens such as Or a delay in the onset of death is selected for; however, such a delay does not guarantee the survival of the host species. > myxamatosis are deliberately selected for virulence and then introduced > to a naive wild population, extinction only occurs locally with the > pathogen rapidly evolving towards lowered virulence as it squeezes > through population bottlenecks. The myth of the exterminator pathogen is Are there covariates of the phenotype(s) "virulence" that might also explain this result? > just that. Consider the evolutionary achievements of viruses with > different levels of virulence AIDS vs Ebola. AIDS is not a wipeout virus At best, a bold hypothesis, not a conclusion. > it has propagated itself widely. Ebola never gets going in the human > population as it kills all the hosts before enough transmissions take > place to achieve any growth. The disease model just doesn't wash for the Ebola has not spread widely *yet* due to the speed of its virulence. The creative nature of natural selection upon which Mark Leney's comments are predicated is real; however, rejection of a Pleistocene hypothesis with the comments is a bit of a stretch. Selection relies on the variation presented to it by mutation; it cannot determine a priori that the next host individual is the last. And the AIDS example is poor; presumedly, cultural evolution can occur at the speed of information transmission; my guess is that our species has and is responding in advance of exposure. > whole continent. There may be counterexamples of widespread demise due to virions, etc; if so , I'd like to hear of them. Moreover, the hypothesis of a megapathogen should be made testable somehow. _________________________________________________________________ JAMES LYONS-WEILER PH: (702) 359-6391 ECOLOGY, EVOLUTION AND FAX: (702) 784-4583 CONSERVATION BIOLOGY/186 eMAIL: weiler@grass.ers.unr.edu 1000 VALLEY ROAD THE UNIVERSITY OF NEVADA, RENO RENO, NEVADA 89512-0013 _________________________________________________________________ From: PO3::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 16-APR-1996 10:11:29.11 To: Multiple recipients of list QUATERNARY CC: Subj: Re: PLEISTOCENE EXTINCTIONS Elin Smith has suggested: >I'd suggest that if the cause was disease the animials who had the >disease were the predators rather than the herbivores. If predator >populations were reduced herbivore populations would boom, overgraze then >bust and we would have the pattern of extinctions we now see (ruminants and >smaller types). > >I have suggested that H. sapiens hunting further up on the food chain >would have a similar impact. I will be presenting a computer simulation >of same at CANQUA and will have a poster at AMQUA - The computer simulations might work very well, but a reality check might be in order. It is extremely rare to find human populations hunting predators as a source of much of anything except "macho points". They're far more rare on the landscape, far more dangerous to pursue, and except in exotic cases, not on the menus of any major group of indigenous peoples. A major epidemic among grazing populations is potentially enticing, but given the vast disparity of animals involved (from bison to musk oxen to mammoths and mastodons - which are less closely related to each other than humans are to gibbons), AND the thousands of years over which the extinctions took place, this seems extremely unlikely. Microbial pathogens are extremely specific in terms of hosts; a common benign parasite of white-tail deer, for example, is lethal to caribou. Dogs and cats have their own diseases - though both are descendents of predators. Even when lethal pathogens are in animal populations, they affect a relatively small proportion of that population unless the animals are genetically susceptable and/or crowded into unnaturally dense population concentrations (large-scale farms raising white leghorn chickens come to mind as a classic example). Hunting undoubtedly exerted some pressure, and environmental change was dramatic and rapid. The two combined may well have proved sufficient. - Bob Nelson *********************************************** Robert E. Nelson Phone: [207] 872-3247 Department of Geology FAX: [207] 872-3555 Colby College e-mail: renelson@colby.edu 5804 Mayflower Hill Drive Waterville, Maine 04901-8858 "Good science consists mostly of play disguised as work." - E. O. Wilson *********************************************** From: PO2::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 16-APR-1996 10:48:05.82 To: Multiple recipients of list QUATERNARY CC: Subj: Re: PLEISTOCENE EXTINCTIONS On Tue, 16 Apr 1996, Robert E. Nelson wrote: > > The computer simulations might work very well, but a reality check might be > in order. It is extremely rare to find human populations hunting predators > as a source of much of anything except "macho points". They're far more > rare on the landscape, far more dangerous to pursue, and except in exotic > cases, not on the menus of any major group of indigenous peoples. That may be partly true, but ecological theory predicts that human hunters of animal X and non-human hunters of animal X would be in competition. Since predators are also dangerous to humans, we should expect humans to spend some effort knocking them off. The "mocho points" explanation is a purely cultural one. Underlying such behaviors may well be an ecological explanation. Maa-speaking pastoralists hunt lions for macho points, but in so doing reduce damage to their herds. Doday, the Ju/hounsi bushmen who have taken up cattle herding have specifically petitioned to be able to hunt lions for the expressed purpose of removing their theat to their herds and the personal threat to them. Efe pygmies hate leopards, and fear them, but also revel in killing them, not for macho points but because they get nervous with leopards hanging around., etc. Also, Elin's idea is especially interesting, as you point out, because it is ammenable to computer simulation. In a sense, this makes it testable in an interesting way. Cheers, GTL Greg Laden Department of Anthropology Harvard University 11 Divinity Avenue Cambridge MA 02138 gladen@fas.harvard.edu From: PO3::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 16-APR-1996 16:40:51.83 To: Multiple recipients of list QUATERNARY CC: Subj: Re: PLEISTOCENE EXTINCTIONS I would suggest that one only need to reduce predator populations around 1% to get major instability in herbivore populations. Since animals other than those hunted by H. sapiens are extinct a wider ecological change is indicated. A boom bust scenario would select for smaller and more energetically efficient animals (ruminants vs cecal digesters). I would observe that in Africa, at the beginning of this century, when rinderpest was introduced by Europeans, wildebeast and buffalo populations were reduced such that many lions became "man eaters". This was despite the fact that African lions have long experience of how dangerous it is to eat men, since they tend to retaliate. The introduction of a new predator tends to reduce the population levels of other predators. If the old predators, not having experience of H. sapiens, turned to eating H. sapiens, then the "macho point" scenario is not that far fetched. A disease that attacked predators might have the same impact. elin Elin Whitney-Smith elin@tmn.com http://www.well.com/user/elin On Tue, 16 Apr 1996, Robert E. Nelson wrote: > Elin Smith has suggested: > >I'd suggest that if the cause was disease the animials who had the > >disease were the predators rather than the herbivores. If predator > >populations were reduced herbivore populations would boom, overgraze then > >bust and we would have the pattern of extinctions we now see (ruminants and > >smaller types). > > > >I have suggested that H. sapiens hunting further up on the food chain > >would have a similar impact. I will be presenting a computer simulation > >of same at CANQUA and will have a poster at AMQUA - > > The computer simulations might work very well, but a reality check might be > in order. It is extremely rare to find human populations hunting predators > as a source of much of anything except "macho points". They're far more > rare on the landscape, far more dangerous to pursue, and except in exotic > cases, not on the menus of any major group of indigenous peoples. > > A major epidemic among grazing populations is potentially enticing, but > given the vast disparity of animals involved (from bison to musk oxen to > mammoths and mastodons - which are less closely related to each other than > humans are to gibbons), AND the thousands of years over which the > extinctions took place, this seems extremely unlikely. Microbial pathogens > are extremely specific in terms of hosts; a common benign parasite of > white-tail deer, for example, is lethal to caribou. Dogs and cats have > their own diseases - though both are descendents of predators. Even when > lethal pathogens are in animal populations, they affect a relatively small > proportion of that population unless the animals are genetically > susceptable and/or crowded into unnaturally dense population concentrations > (large-scale farms raising white leghorn chickens come to mind as a classic > example). > > Hunting undoubtedly exerted some pressure, and environmental change was > dramatic and rapid. The two combined may well have proved sufficient. > - Bob Nelson > *********************************************** > Robert E. Nelson Phone: [207] 872-3247 > Department of Geology FAX: [207] 872-3555 > Colby College e-mail: renelson@colby.edu > 5804 Mayflower Hill Drive > Waterville, Maine 04901-8858 > > "Good science consists mostly of play disguised as work." > - E. O. Wilson > *********************************************** > From: PO3::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 17-APR-1996 12:25:13.90 To: Multiple recipients of list QUATERNARY CC: Subj: Re: PLEISTOCENE EXTINCTIONS My two cents worth on the current extinction discussion....all of this is quite interesting and far from a "dead horse" (or mammoth) topic, as some have suggested. The disease possibility is intriguing, but again one must ask what sort of "megadisease" would have wiped out so many species at this particular time--why not earlier, etc.etc. One might also look to islands for well documented examples of rapid human induced extinctions. This is particualry well demonstrated in the Pacific, esp. as it relates to birds. Also, there are examples from the Mediterranean islands--for example, in Sardinia and Malta there are fairly well documented cases of long-term co-existence prior to extinction. A problem is how far back all this can be projected. Our own work on Cyprus has pretty convincingly demonstrated a relatively rapid extinction event (ca. 500 years or so) at ca. 10,000 b.p. This involved the endemic pygmy hippopotamus and the first occupants of the island, at Akrotiri Aetokremnos. Here we have over 300 MNI (along with several birds, a few pygmy elephants, and lots of marine shell) associated with well-dated cultural materials. On Cyprus, however, a rapid human extinction is perhaps more plausible. On an island, with its unique biogeography, humans can have a more profound effect. This would have been especially true in a place like Cyprus, particuarly since there were no native predators. If the animals were already under stress, due to climatic change or whatever, humans could more easily have dispatched the naive "mini-megafauna." Alan Simmons, Dept. Anthropology, University of Nevada, Las Vegas From: PO2::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 17-APR-1996 19:02:51.26 To: Multiple recipients of list QUATERNARY CC: Subj: bison survival At the Alaska Anthropological Association meetings this month there was a symposium in honour of Dale Guthrie. At that symposium Larry Todd (Anthropology, Colorado State University) presented an interesting paper on bison which included analysis of bison size (based on limb bones, not horn cores) for very securely dated individuals from bone beds in the U.S. plains region. There was a dramatic decrease in size over a very short time (maybe 11ka to 9ka ?). This not only coincides with a period of significant climatic and geological change, but also with the arrival of human predators. Some years ago I read a paper (by Grover Krantz ?) suggesting that it was human predation which allowed the bison to survive. I can't remember the argument in detail, but it could be that intensive human predation resulted in decreased bison size, and that decreased size was an adaptive advantage in the rapidly changing environments of the time. However, there were a number of ungulate species which survived the extinctions at the end of the Pleistocene in North America, including wapiti (Europeans read red deer), moose (Europeans read elk), mountain goat, bighorn sheep, caribou, various deer, pronghorn antelope. Most of these were not intensively hunted by humans, nor did they all experience the dramatic change in size and morphology seen in bison. I don't think that one should necessarily assume a single cause for extinctions or survivals in a particular period. Different species (and even different populations of the same species) may have become extinct as a result of different chains of events. While the ultimate cause is probably due to global/astronomical changes, it is simplistic to search for single causes. At the species level there were no doubt many "routes" to extinction. Jon Jon Driver Chair, Department of Archaeology Simon Fraser University Burnaby BC V5A 1S6 Canada From: PO2::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 24-APR-1996 09:30:54.69 To: Multiple recipients of list QUATERNARY CC: Subj: Re: PLEISTOCENE EXTINCTIONS On Tue, 16 Apr 1996, Elin W. Smith wrote: > > I would observe that in Africa, at the beginning of this century, when > rinderpest was introduced by Europeans, wildebeast and buffalo > populations were reduced such that many lions became "man eaters". This > was despite the fact that African lions have long experience of how > dangerous it is to eat men, since they tend to retaliate. > But this comes back to my earlier point, although the rinderpest caused huge short term changes in ecology there were no extinctions. Mark Leney Department of Biological Anthropology University of Cambridge mdl1002@cus.cam.ac.uk From: PO2::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 24-APR-1996 10:57:42.48 To: Multiple recipients of list QUATERNARY CC: Subj: Re: PLEISTOCENE EXTINCTIONS >On Tue, 16 Apr 1996, Elin W. Smith wrote: > >> >> I would observe that in Africa, at the beginning of this century, when >> rinderpest was introduced by Europeans, wildebeast and buffalo >> populations were reduced such that many lions became "man eaters". > and on 24 Apr 1996, Mark Leney wrote: >But this comes back to my earlier point, although the rinderpest caused >huge short term changes in ecology there were no extinctions. I think Mark has the upper hand here. Just off hand, I know of no historic extinctions due to disease and, as a biologist, I would expect disease-caused extinction only of very small populations with limited genetic variation or, alternatively, of populations already under extreme population stress from other factors. Also, it might be noted that a number of Beringian populations became extinct despite being in contact with the Old World and presumably co-evolved with Old World disease organisms. Cheers! Art Harris Laboratory for Environmental Biology, Centennial Museum University of Texas at El Paso, El Paso, TX, USA 79968-0519 Tel. (915) 747-6985, Fax (915) 747-5808, e-mail aharris@utep.edu Visit our Web Site at http://www.utep.edu/~leb/home.html From: PO2::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 24-APR-1996 14:38:51.40 To: Multiple recipients of list QUATERNARY CC: Subj: Re: PLEISTOCENE EXTINCTIONS I agree that disease, and especially disease of herbivores, is inadequate. I am interested in rinderpest because it prompted lions to turn "man eaters". My theory is that H. sapiens reduced carnivore populations sufficiently so that there was a boom of herbivore populations, creating a highly competitive situation, followed environmental eshaustion and a herbivore population crash. The only place I see disease having the same effect is if it were a disease of predators. This >> was despite the fact that African lions have long experience of how >> dangerous it is to eat men, since they tend to retaliate. >> > > >But this comes back to my earlier point, although the rinderpest caused >huge short term changes in ecology there were no extinctions. > > > > >Mark Leney >Department of Biological Anthropology >University of Cambridge >mdl1002@cus.cam.ac.uk > > From: PO4::"QUATERNARY@MORGAN.UCS.MUN.CA" "Research in Quaternary Science" 24-APR-1996 17:12:11.77 To: Multiple recipients of list QUATERNARY CC: Subj: Re: PLEISTOCENE EXTINCTIONS Elin Whitney-Smith wrote (in part): >My theory is that H. sapiens reduced carnivore populations >sufficiently so that there was a boom of herbivore populations, creating a >highly competitive situation, followed environmental eshaustion and a >herbivore population crash. My objections to this hypothesis tend to be similar to those concerning extinction by disease--namely, that this doesn't seem to be the way things happen in the present. We see herbivore population explosions resulting in major dieoffs due to starvation and disease, but we don't see the populations going extinct. There normally is enough individual and genetic variation in populations so that enough individuals survive the resource bottleneck to carry on; note also that density dependent factors commonly put the brakes on population growth long before population size results in *utter* catastrophy. Also, as I understand it, predator pressure usually is not the primary factor controling herbivore population numbers. Cheers :-] Art Harris Laboratory for Environmental Biology, Centennial Museum University of Texas at El Paso, El Paso, TX, USA 79968-0519 Tel. (915) 747-6985, Fax (915) 747-5808, e-mail aharris@utep.edu Visit our Web Site at http://www.utep.edu/~leb/home.html