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from article Dendrochronology

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Ring patterns showing complacent and sensitive ring series. (a) Climate has minimal effect on ring widths when trees have ample moisture every year. (b) Maximum ring-width variations occur on sites where growth is limited by factors that vary from…

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from article Dendrochronology

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Core being taken from a tree with an increment borer. (Courtesy of Laboratory of Tree-Ring Research, University of Arizona)

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from article Dendrochronology

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Chronology building. Chronologies are extended backward in time by matching patterns of wood samples whose ages overlap.

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from article Dendrochronology

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Skeleton plot (top) from an idealized tree-ring sequence in a specimen (bottom). Ring widths are represented by vertical lines in inverse proportion; that is, tall lines represent narrow rings. An exceptionally wide ring is designated by the letter…

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from article Dendrochronology

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Bristlecone pines, which attain ages of more than 4000 years, form the basis for the second longest chronology yet developed. (Courtesy of Laboratory of Tree-Ring Research, University of Arizona)

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from article Paleoindian

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Location of some important North American Paleoindian sites during the late-Pleistocene Ice Age.

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from article Fossil primates

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Representatives of living primate families. (Copyright © McGraw-Hill Education)

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from article Fossil primates

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Carpolestes simpsoni, a 55.5-million-year-old plesiadapiform from Wyoming: (a) skeleton as recovered, laid out in approximate anatomical position; (b) reconstruction in life stance on a tree branch; elements in dark gray are known; (c) external…

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from article Fossil primates

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Cranium of the omomyoid tarsiiform Teilhardina asiatica, from deposits dated approximately 55 MYA in China: (a) dorsal (top) view as found; (b) left lateral reconstruction. (Credit: Xijun Ni)

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from article Fossil primates

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Anjohibe (Madagascar) specimen of Palaeopropithecus ingens (an extinct lemur), mounted in a probable habitat posture. (Credit: American Geological Institute)

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from article Fossil primates

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Partly reconstructed skeleton (casts) of Paracolobus chemeroni, a 3.2-million-year-old colobine monkey from Kenya, on exhibit at the American Museum of Natural History in New York. (Credit: Eric Delson)

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from article Fossil primates

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Reconstructed skeleton of Proconsul heseloni, an early hominoid (23–14 MYA) from East Africa. Known parts are shaded. (Credit: R. L. Ciochon and R. S. Corruccini)

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from article Paleolithic

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Relationship between time, hominid taxa and major cultural developments during the Paleolithic.

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from article Paleolithic

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Oldowan pebble tools from Bed I, Olduvai Gorge. (After M. D. Leakey, Olduvai Gorge, vol. 3, p. 27, Cambridge University Press, 1971)

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from article Paleolithic

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Late Acheulean hand axes from England. (After D. A. Roe, The Lower and Middle Palaeolithic Periods in Britain, Routledge Kegan Paul, 1981)

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from article Paleolithic

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Middle Paleolithic (Mousterian) flake tools from France. (After R. G. Klein, Ice-Age Hunters of the Ukraine, University of Chicago Press, 1973)

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from article Paleolithic

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Upper Paleolithic flake and blade artifacts from the Ukraine. (After R. G. Klein, Ice-Age Hunters of the Ukraine, University of Chicago Press, 1973)

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from article Paleolithic

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Upper Paleolithic art objects from the Ukraine. (After R. G. Klein, Ice-Age Hunters of the Ukraine, University of Chicago Press, 1973)

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from article Fossil apes

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Reconstructions and partial reconstructions of the craniums of fossil apes: (a) Proconsul, (b) Afropithecus, (c) Oreopithecus, (d) Ouranopithecus, (e) Sivapithecus, and (f) Ankarapithecus.

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from article Fossil apes

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Cladogram of the evolutionary relationships of the key fossil and living apes. Broken lines indicate uncertain relationships.

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from article Anthropology

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Fossil skulls of four different species of Homo (clockwise from upper left): Homo neanderthalensis, Homo antecessor, Homo erectus, and Homo sapiens. Each skull shows different anatomical variations. (Credit: creativemarc/Shutterstock)

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from article Anthropology

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The indigenous inhabitants of Siberut Island (West Sumatra, Indonesia) are known as the Mentawai people. They live a seminomadic hunter-gatherer life in the coastal and rainforest environments of the island. (Credit: Chanwit Whanset/Shutterstock)

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from article Domestication

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An Egyptian painted-wood sculpture of a man holding a plow pulled by two oxen. This early representation of domesticated animals is dated to approximately 1900 BCE. (Credit: Metropolitan Museum of Art, New York)

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from article Domestication

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Wheat (genus Triticum) is one of the earliest domesticated cereal crops. (Credit: Emilio Ereza/Pixtal/AGE Fotostock)

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from article Domestication

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Dogs are the earliest known domestic animals. They have been used by humans to help herd other domesticated animals, such as sheep. (Credit: Dan Brandenburg/Getty Images)

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