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Primates and Human Evolution

•  Diversification of Primates –  New world & old world –  Apes

•  Origin of humans –  Many species of hominins –  Out of Africa

•  Biodiversity & Conservation

April 29, 2019

Diversification of Primates

Phylogeny of the Primates (a) Gibbon (b) Orangutan

(c) Gorilla

(d) Chimpanzees

(e) Bonobos

Figure 34.45

Figure 23.56 Neoteny in the Evolution of Humans

Figure 23.55 A Phylogenetic Tree of Hominids

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•  Misconception: Early hominins were chimpanzees

– Correction: Hominins and chimpanzees shared a common ancestor

•  Misconception: Human evolution is like a ladder leading directly to Homo sapiens

– Correction: Hominin evolution included many branches or coexisting species, though only humans survive today

Humans Evolved among the Primates•  Early modern humans (H. sapiens)

expanded out of Africa 70,000 to 60,000 years ago.

•  About 35,000 years ago, H. sapiens moved into the range of H. neanderthalensis.

Present-day people participating in the 1000 Genomes project inherited one of three versions, or haplotypes, of immunity genes. Neandertals passed haplotype III to all non-Africans, and some Asians also inherited Neandertal haplotype IV. Those versions of the immunity genes may have helped human ancestors fend off new pathogens, but now contribute to allergies.

The Tree of Life

Animal Phylogeny How many species are there? •  about 1.5 million species have been named

•  estimated to be between 5 and 30 million species on Earth

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�an inordinate fondness for beetles�

•  Basset Arthropod diversity estimate, Science Dec 2012

What is the total number of species?

Species richness is highest in the tropics

Plant Species Richness

Mammals

Biodiversity “hotspots”

Equator

Terrestrial biodiversity hot spots

Marine biodiversity hot spots

Levels of Biological Diversity

Genetic diversity in a vole population

Species diversity in a coastal redwood ecosystem

Community and ecosystem diversity across the landscape of an entire region