The Triumph Of Uniformitarianism
Even before Darwinian theory emerged, Catastrophism came under attack, principally from the Scottish geologist Charles Lyell who was following arguments made earlier by his fellow countryman James Hutton. In his Principles of Geology, published in three volumes in the 1830s, Lyell argued that the geological processes we observe today such as erosion by wind and rain, earthquakes and volcanoes, and so on are responsible for all geological changes that have occurred throughout Earth history. He...
Mass Extinctions Are Qualitatively Different
The University of Chicago paleontologist David Jablonski has investigated the nature of that selection by comparing the pattern in background and mass extinction periods. During background extinction, several factors contribute to the protection of a species from extinction. Species that are geographically widespread resist extinction, for instance. Likewise, marine species that send their larvae far and wide drifting with the currents resist extinction, for similar reasons. A group of related...
a brief history of discovery
The first discoveries of Homo erectus were made in 1891 and 1892 in Java, Indonesia, by Eugene Dubois, a Dutch medical doctor, who had gone there specifically to search for the missing link. The specimens were of a skull cap and a complete thigh bone, or femur, which indicated that the creature had walked upright. Although he was initially ambivalent over the human nature of his fossil find, Dubois eventually came to name the species Pithecanthropus erectus, or upright ape man, inspired in part...
The earuest known homo
The strongest claims for evidence of Homo earlier than 2 million years come from the recent reassessment of a cranial fragment from Kenya and a recently discovered mandible from the site of Uraha in Malawi, which lies between East Africa and South Africa. In 1967, the temporal bone side of the head of a hominin was discovered in the Chemeron formation near Lake Baringo, in central Kenya. The structure around the ear-specifically the mandibular fossa, or jaw joint is diagnostic of Homo. The...
Some General Patterns
Three key points stand out in any review of the evolution of the catarrhines see figure 16.1 . First, the fossil record of the group generally does not overlap with the geographic areas where catarrhines are most abundant today. The early fossil record is concentrated in North Africa and Eurasia, with some specimens found in East and southern Africa. Modern Old World monkeys and apes are most abundant in the forests of sub-Saharan Africa and Southeast Asia. This pattern may reflect real changes...
Human Evolution As Narrative
In the early twentieth century, explanations of human evolution were often constructed as stories, particularly hero myths. Human ancestors were seen as overcoming great challenges, and finally triumphing. Part of the story was an implicit inevitability, that Homo sapiens was an inevitable outcome of evolution. Even today, because the narrative form is so powerful and seductive, it is hard to avoid. One of the species specific characteristics of Homo sapiens is a love of stories, noted Glynn...
The Power Of Natural Selection
Natural selection, as enunciated by Darwin, is a simple and powerful process that depends on three conditions. First, members of a species differ from one another, and this variation is heritable. Second, all organisms produce more offspring than can survive. Although some organisms, most notably large-bodied species and those that bestow a lot of parental care, produce few offspring while others may produce thousands or even millions, the same rule applies. Third, given that not all offspring...
Distribution Of Living Primates
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The Changing Position Of Homo Erectus
Homo erectus was long assumed to be the species intermediate between early Homo and Homo sapiens. Now, however, many scholars believe that the specimens assigned to Homo erectus in fact represent two species, Homo erectus and Homo ergaster, with ergaster being the precursor of erectus. Whatever the true interpretation, it is clear that the emergence of erectus ergaster represented a new grade of hominin, with a very different behavioral repertoire that included the ability to expand its range...
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Bowler PJ. Theories of human evolution. Baltimore Johns Hopkins Press, 1986. Cartmill M. Human uniqueness and theoretical content in paleoanthropology. Int J Primatol 1990 11 173-192. Cartmill M, Pilbeam DR, Isaac GL. One hundred years of paleoanthropology. Am Scientist 1986 74 410-420. Fleagle JG, Jungers WL. Fifty years of higher primate phylogeny. In Spencer F, ed. A history of American physical anthropology. New York Academic Press, 1982. Foley RA. In the shadow of the modern synthesis...
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Aitken MJ, Valladas H. Luminescence dating relevant to human origins. Phil Trans Roy Soc B 1992 337 139-148. Brown FH, et al. An integrated Plio-Pleistocene chronology for the Turkana Basin. In Delson E, ed. Ancestors the hard evidence. New York Alan R Liss, 1985 82-90. Chen Y, et al. The edge of time dating young volcanic ash layers with the argon-40 argon-39 laser probe. Science 1996 274 1176-1178. Deino A, et al. Argon-40 argon-39 dating in paleoanthropology and archeology. Evol Anthropol...
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reasons related to the history of the science of archeology and the impact of new discoveries, the classification of the different periods and stages of cultural development in sub-Saharan Africa and Eurasia represents an uneven mixture of cultural innovation and chronology. See text for details. Bearing in mind the elasticity of stage boundaries, technology development unfolded as follows. The beginning of the ESA corresponds with the first appearance of mode I tools, 2.6 million years ago the...
Key References
Cartmill M. Human uniqueness and theoretical content in paleoanthropology. Int J Primatol 1990 11 173-192. Dawkins R. The blind watchmaker. Harlow Longman, 1986. Eldredge N, Tattersall I. The myths of human evolution. New York Columbia University Press, 1982. Gould SJ. Vision with a vengeance. Natural History Sept 1980 16-20. --. Bound by the great chain. Natural History Nov 1983 20-24. --. Chimp on a chain. Natural History Dec 1983 18-26. --. Spin doctoring Darwin. Natural History July 1995...
Key Problems In Human Evolution
Foley R. Adaptive radiations and dispersals in hominin evolutionary ecology. EvolAnthropol 2002 11 32-37. McHenry HM. Homoplasy, clades, and hominid phylogeny. In Meikle WE, et al., eds. Contemporary issues in human evolution. San Francisco California Academy of Sciences, Memoir 21, 1996. Simons E. Human origins. Science 1989 245 1343-1350. Skelton RR, McHenry HM. Evolutionary relationships among early hominids. J Human Evol 1992 23 309-349. Strait DS, et al. A reappraisal of early hominid...
NatuRE of thE hominin ancEstoR
Fossil evidence of the common ancestor of African apes and humans has yet to be found, not least because the hominoid fossil record in Africa between 4.5 and 8 million years is still sparse. One question is, How would such a creature be recognized Ancestral anatomy can be inferred, based on comparisons among living and extinct hominoids. As a result, the common ancestor is now widely believed to have been intermediate in size between the gibbon and the chimpanzee it is imagined to have been...
Relative Dating Techniques
Relative dating techniques include faunal correlation and paleomagnetism. Geologists and paleontologists have long used fossils to structure prehistory. For instance, the geological time scale for the history of life on Earth is built upon major changes in fossil populations, such as appearances and disappearances of groups. Because they are interested in a finer-scale approach, archeologists and anthropologists often look for evolutionary changes within groups. Among the most important species...
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Boesch C. Hunting strategies of Gombe and Tai chimpanzees. In McGrew WC, et al., eds. Chimpanzee cultures. Cambridge, MA Harvard University Press, 1994 77-91. Foley RA. An evolutionary and chronological framework for human social behavior. Proc British Acad 1996 88 95-117. Kinzey W. Primate models of human behavior. New York SUNY Press, 1987. Nishida T, et al. Meat-sharing as a coalition strategy by an alpha male chimpanzee. In Nishida T, et al., eds. Topics in primatology human origins. Tokyo...
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Broecker WS, Denton GH. What drives glacial cycles Sci Am Jan 1990 48-56. Carson HL. The processes whereby species originate. BioScience 1987 37 715-720. deMenocal PB. Plio-Pleistocene African climate. Science 1995 270 53-59. Foley RA. Speciation, extinction and climate change in hominid evolution. J Human Evol 1994 26 275-289. The evolutionary geography of Pliocene hominids. In Bromate T, Schrenk F, eds. African biogeography, climate change, and hominid evolution. Oxford Oxford University...
Absolute Dating Techniques Radiopotassium Dating
The majority of absolute dating methods are radiometric, which depends on radioactive change in certain minerals. All methods share the same two principles. First, some action Volcanic ash contains potassium-rich minerals, such as feldspar. A small percentage of the potassium exists as a radioisotope, potassium-40, which has argon-40 as one of its decay products. In the laboratory, crystals of feldspar are irradiated with neutrons, which converts the stable potassium-39 isotope to argon-39. The...
Same Story Different Sequences
Traditionally, paleoanthropologists have recognized four key events in human evolution the origin of terrestriality coming to the ground from the trees , bipedality upright walking , encephalization brain expansion in relation to body size , and culture or civilization . While these four events have usually featured in accounts of human origins, paleoanthropologists have disagreed about the order in which they were thought to have occurred. See figure 2.1. For instance, Henry Fairfield Osborn,...
KEY REFERENCES Xsx
Fitch W, Ayala FJ, eds. Tempo and mode in evolution. Washington, DC National Academy Press, 1995. Foley RA. In the shadow of the modern synthesis alternative perspectives on the last 50 years of paleoanthropology. Evol Anthropol 2001 10 5-15. Gould SJ. Darwinism and the expansion of evolutionary theory. Science 1982 216 380-387. Gould SJ, Eldredge N. Punctuated equilibrium comes of age. Nature 1993 366 223-227. Somit A, Peterson SA, eds. The dynamics of evolution. Ithaca Cornell University...
Humans As Inevitable Products Of Evolution
Of course, it is possible to tell stories with similar gusto about nonhuman animals, such as the triumph of the reptiles in conquering the land or the triumph of birds in conquering the air. Such stirring tales are readily found in accounts of evolutionary history look no further than every child's hero, the dinosaur. The fact that the hero of the paleoanthro-pology tale is Homo sapiens ourselves makes a significant difference, however. Although dinosaurs may be lauded as lords of the land in...
The function of AcheuLean handaxes
The function of Acheulean handaxes has long been a subject of speculation. A particularly unlikely explanation is that they were used as lethal projectiles, thrown like discuses as a means of killing prey. More prosaic suggestions hypothesize that they were used as axes or heavy-duty knives. In experimental studies, Indiana University archeologist Nicholas Toth found that handaxes and cleavers were highly effective at slicing tough hide, such as that of elephants. The combination of weight and...
The Singlespecies Hypothesis And Its Demise
Meanwhile, discoveries of fossil hominins, and the stone tools they apparently made, had been accumulating at a rapid pace from the 1940s through 1970s, first in South Africa and then in East Africa. Culture specifically, stone-tool making and tool use in butchering animals became a dominant theme, so much so that hominin was considered to imply a hunter-gatherer lifeway. The most extreme expression of culture's importance as the hominin characteristic consisted of the single-species...
Theory
Evolutionary theory is concerned principally with explanations of species' adaptation to their environment, the origin of species, and the origin of trends within groups of related species, such as the increase in brain size among certain hominins. Some evolutionary biologists argue that all evolutionary change is the outcome of the accumulation of small changes through natural selection. Others see different mechanisms as being important, too. One of the most important phenomena that a...
Absolute Dating Techniques Thermoluminescence And Electron Spin Resonance
Two relatively new dating techniques depend on the principle that electrons in certain minerals become excited to higher energy levels when irradiated by radioisotopes of uranium, thorium, and potassium, which occur naturally in the ground and in cosmic rays. The radioactive rays knock off the negatively charged electrons from atoms, leaving positively charged holes. These electrons diffuse through the crystal lattice and usually recombine with other holes, returning to the ground state. But...
Our Place In Nature
The Darwinian revolution forced people to face the fact that humans are part of nature, not above nature. Nevertheless, anthropologists struggled with explaining the specialfeatures ofHomo sapiens, such as our great intelligence, our sense of right and wrong, our esthetic sensibilities. Only since the latter part of the twentieth century have anthropologists fully embraced naturalistic explanations of our special qualities. In 1863 Charles Darwin's friend and champion, Thomas Henry Huxley,...
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Britten RJ. Rates of DNA sequence evolution differ between taxo- nomic groups. Science 1986 31 1293-1298. Hillis DM, et al. Application and accuracy of molecular phylogenies. Science 1994 264 671-677. Kimura M. Molecular evolutionary clock and the neutral theory. J Mol Evol 1987 26 24-33. King MC, Wilson AC. Evolution at two levels in humans and chimpanzees. Science 1975 188 107-116. Lewin R. Patterns in evolution a molecular view. New York W. H. Freeman, Scientific American Library, 1996....
The Stage Is Set For The Piltdown Forgery
At the turn of the century several interrelated intellectual debates were brewing, one of which focused on the order in which the major anatomical changes occurred in the human lineage. One notion was that the first step on the road to humanity was the adoption of upright locomotion. A second held that the brain led the way, producing an intelligent but still arboreal creature. See figure 3.3. It was into this intellectual climate that the perpetrator of the famous Piltdown hoax a chimera of...
Australopithecines
The abundance of fossil remains of australopithecine species, particularly of afarensis, africanus, and boisei robustus, allows insight into how these creatures lived that is not possible for other pre-Homo hominins. Australopithecines were apelike from the neck up and humanlike from the neck down. Though apelike in parts of the cra-mum, the australopithecine face does not protrude as much as in apes, and the cheek teeth are large and flat, while the anterior teeth were relatively smaller,...
Establishment Of Population Genetics
Darwin was well aware that members of a species vary, and that these variations are heritable his observations of natural populations and experiments with domestic breeding were proof of that ability. He was not familiar with the basis of inheritance, however. Although the rules of inheritance were discovered by the Austrian monk Gregor Mendel in the early 1860s, the results of his work remained generally unknown until two decades after Darwin's death, in 1882. From observations on the progeny...
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Andrews P. Paleoecology and hominoid paleoenvironments. Biol Rev 1996 71 257-300. Andrews P, Pilbeam D. The nature of the evidence. Nature 1996 379 123-124. Beard KC, et al. Earliest complete dentition of an anthropoid primate from the late Middle Eocene of Shanxi Province, China. Science 1996 272 82-85. Begun D. Relations among the great apes and humans. Yearbook Physical Anthropol 1994 37 11-64. Benefit BR, McCrossin ML. Middle Miocene hominoid origins. Science 2000 287 2375-2378. de Bonis L,...
Hominin Origins In Terms Of Human Qualities
Once Darwin's work firmly established evolution as part of mainstream nineteenth-century intellectual life, scientists had to account for human origins in naturalistic rather than supernatural terms. More importantly, as we saw in the previous two units, they had to account for the evolutionary origin of special qualities of humankind, those that appear to separate us from the world of nature. This issue posed a formidable challenge and the response to it set the intellectual tone in...
Technologies
About half a million years after the first appearance of Homo ergaster, a new form of stone-tool technology is seen in the archeo-logical record. Known as the Acheulean, the assemblage is characterized by large forms, particularly the handaxe, which required greater skill in conceptualization and manufacture. They would have allowed more extensive manipulation of animal resources. The Acheulean is seen first in Africa, and later in Eurasia, but not in East Asia. It remained relatively unchanged...
EanY hypotheses and recem developments
During the 1960s and early 1970s, paleoanthropologists considered hunting to be the primary human adaptation, a notion that has deep intellectual roots, reaching back as far as Darwin's Descent of Man. The apogee of the hunting hypothesis was marked by a Wenner-Gren Foundation conference in Chicago in 1966, titled Man the Hunter. The conference not only stressed the idyllic nature of the hunter-gatherer existence the first affluent society as one authority termed it but also firmly identified...
The Physical Context Of Evolution
The physical environment, in terms of geography and climate, has been recognized as being an important driver of evolutionary change. Plate tectonics can separate previously united communities, or unite previously separate communities, with profound evolutionary consequences. Climate change can effect speciation and extinction, depending on species' resource needs and tolerances. Two factors are recognized as influencing the evolution of new species and the extinction of existing species. First...
Key Questions
Did the intellectual framework provided by the great Chain of Being lead naturally to the idea of the evolution of species Why did the perception of Man's place in nature not change much in some ways between pre- and post-Darwinian eras Why has the notion of progress become such an integral part of evolutionary thinking within Western philosophy, particularly in relation to human evolution Does the evolution of qualitatively novel characteristics require qualitatively novel explanations but...
Orrorin Tugenensis
Beynon AD, et al. On thick and thin enamel in hominoids. Am J Physical Anthropol 1991 86 295-309. Bromage TG, Dean MC. Re-evaluation of the age at death of immature fossil hominids. Nature 1985 317 525-527. Conroy GC, Vannier MW. Dental development of the Taung skull from computerized tomography. Nature 1987 329 625-627. Macho GA, Wood BA. Role of time and timing in hominid dental evolution. Evol Anthropol 1995 4 17-31. Mann AE, et al. Maturational patterns in early hominids. Nature 1987 328...
Jessica Thompson Anthropology
The pattern of treatment of issues in this new edition follows that established with the fourth edition nevertheless there are important changes. For instance, in the preface to the previous edition I wrote, The five years since the third edition of Human Evolution An Illustrated Introduction have been an extraordinarily productive time for paleoanthropology, not least because of the number of new species of early humans that had been discovered. The same can be said of the period between the...
Relationship Among The Great Apes Reconsidered
Arguments about the relatedness between humans and African apes were mirrored by a reconsideration of the re-latedness among the apes themselves. In 1927, G. E. Pilgrim had suggested that the great apes be treated as a natural group that is, evolutionarily closely related , with humans viewed as more distant. This idea eventually became popular and remained the accepted wisdom until molecular biological evidence undermined it in 1963, via the work of Morris Goodman at Wayne State University....
Psychological Anthropology Evolution Question
How different are the patterns of bone accumulations at the Olduvai sites from those at pure carnivore sites How are cutmarks distributed on Olduvai bones, and what does this pattern imply about the integrity of the bones that were transported to the sites Can a distinction be made between evidence for hunting as against evidence for early scavenging What kind of social organization might be implied by the central-place foraging hypothesis
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Bogin B. The evolution of human childhood. BioScience 1990 40 16-25. Charnov EL, Berrigan D. Why do female primates have such long lifespans and so few babies Or life in the slow lane. Evol Anthropol 1993 1 191-194. Foley R. Humans before humanity. Oxford Blackwell, 1995. Harvey P, Martin R, Clutton-Brock T. Life histories in comparative perspective. In Smuts BB, Cheney DL, Seyfarth RM, Wrangham RW, Struthsaker TT, eds. Primate societies. Chicago The University of Chicago Press, 1986 181-196....
Early Tool Technologies
The earliest stone artifacts, simple flakes and cores, appear in the archeological record some 2.5-plus million years ago. It has long been assumed that the tool makers were members of the genus Homo. However, several lines of evidence indicate that australopithecines might have been the first tool makers. Although these earliest tools look very simple, they in fact require considerable skill, skill that is beyond modern apes. Stone artifacts have been collected by amateurs and professionals...
Limitations Of Molecular Systematics
Today, molecular approaches to systematics are recognized as less simple, and therefore less immediately reliable, than previously supposed for several reasons. For instance, it is now recognized that the dynamics of mutation are highly complex, including the fact that not all regions of a gene or other regions of DNA are equally susceptible to change indeed, some regions are highly susceptible to similar kinds of change. For this reason, convergence can and does occur in DNA sequences....
Consequences of sociaL organization
Given these underlying influences, says Wrangham, several predictions can be made in terms of behaviors within and between groups. For instance, intense social interaction-grooming and so on-is expected among females in female-bonded groups, but is less frequent in non-female-bonded FICURE 13.3 Distribution, with small resource patches When food exists in patches too small to support more than one mature individual, females will forage singly with their offspring . If a male can defend a...
Molecular Systematics
Genetic evidence has recently taken its place alongside morphology, creating the approach known as molecular systematics. Various kinds of data are relevant here, including DNA sequences, comparison of immunological reactions of proteins, comparison of electrical properties of proteins gel electrophoresis , and DNA-DNA hybridization, which effectively compares the entire genetic complement of one species with that of another. All of these methods, with the exception of DNA sequence data,...
Hominin Beginnings
15 Ape and Human Relations Morphological and Molecular Views 19 The Earliest Hominins a History of Discoveries APE AND HUMAN RELATIONS MORPHOLOGICAL AND MOLECULAR VIEWS Anthropologists have for years argued over the relationship between humans and great apes. Until relatively recently, the great apes were considered each other's closest relatives, with humans being separate. Now, however, based on anatomical and especially molecular evidence, it has become apparent that humans and chimpanzees...
The Influence Of Plate Tectonics
If new species preferentially arise in small, isolated populations allopatric speciation rather than in large, continuous populations sympatric speciation , as modern evolutionary theory holds, then processes that promote the establishment of small isolated populations can be regarded as a potential engine of evolution. The physical environment provides two means by which this process might occur. First, topography on local and global scales may change, principally through the mechanism of...
Jaws And Teeth
Jaws and teeth are a rich source of information about a species' subsistence and behavior. In hominoids there was an evolutionary trend toward shorter jaws and a deeper face, giving a less snout-like aspect. This trend was particularly exaggerated in hominins. Eruption patterns give insight into a species' life history. And microwear patterns on the surface of teeth give strong clues to a species' diet. In this unit we will examine four facets of hominoid dentition the overall structure of jaws...
Apes Become Acceptable As Ancestors
During the 1930s and 1940s, the anti-ape arguments of Osborn and Wood Jones were lost, but Gregory's position did not immediately prevail. Gregory had argued for a close link between humans and the African apes on the basis of shared anatomical features. Others, including Adolph Schultz and D. J. Morton, claimed that although humans probably derived from apelike stock, the similarities between humans and modern African apes were the result of convergent evolution. That is, two separate lines...