BI 215 CH 19

order primates

order primates

Prosimians, Monkeys, Apes, Humans.

chimpanzees; bonobos

Humans are most closely related to __________ and ________

Superfamily Hominoidea

: humans and all four great apes (chimpanzees, gorillas, orangutans, and gibbons) ‘hominoids’.

Family Hominidae

Humans & Chimpanzees, Gorillas, Orangutans.

Subfamily Homininae

Humans & Chimpanzees, Gorillas

Tribe Hominini

Humans & Chimpanzees

Subtribe Hominina

Humans & extinct humans (‘Hominins’)

6-7; Homo sapiens

Fossils allow the reconstruction of the evolutionary events since the divergence of the early hominid lineage from chimpanzees (___ MYA) up to the emergence of _____ ______.

Africa

There is strong morphological & DNA evidence that modern humans originated in _____

Human-Chimp Ancestor 6-7 MYA

an arboreal ape with a small brain; long arms; quadrupedal walker; opposable big toe

Hominins

Lots of intermediate species: Earliest hominin fossils (7 to 2 MYA) found only in Africa; Earliest hominin fossils outside of Africa 2 MYA, all species of Homo have anatomical features similar to ours. Ten extinct species of Homo (‘missing link’ not missing!). Abundant fossil evidence for shared ancestry of H. sapiens with extinct hominins.

7; 2

Earliest hominin fossils (_ to _ MYA) found only in Africa

2

Earliest hominin fossils outside of Africa _ MYA,

9; 24; 4

HOMININ FOSSILS (_ GENERA; __ SPECIES) FALL INTO _ GROUPS

7 to 4.4 MYA

(how long ago)Earliest hominins. All from Africa

4 to 2.5 MYA

Australopithecines All from Africa

4 to 2.5 MYA

Robusts: All from Africa

2.5 MYA until now

Genus Homo: Early and Modern Humans. Originated in, & spread throughout Africa; Colonized other parts of the world several times more recently

Upright; bipedal

_______ posture & ______ walking evolved early in hominin evolution

Human vs Chimp

A) foramen magnum aligned directly beneath skull; B) pelvis shortened & broadened; C) femur elongated & angled inward; foot arched for walking & hallux (big toe) aligned with other toes rather than opposable

African apes stood upright around 6 MYA

Erect posture & bipedal locomotion; Foot and hand evolution: 3.8 MYA ‘Lucy’ walked upright – fossil footprints in volcanic ash in Tanzania: Fossil footprints not made by chimp or human.

6; 7

evolution of skull features from chimp to human took _ to _ m years

chimp

small brain case; large jaw; big teeth; big brow ridge

human

large brain case, small jaw, small teeth, no brow ridge. upright posture & bipedalism evolved early; increased brain size and tool use arose later (in genus Homo)

human characters

Walking: bipedal; Spine: s-shaped; Pelvis: bowl-shaped ; Legs longer; Arms shorter; Big toe: straight; Thumb: opposable; Thick body hair: lost ;Cranium & brain: bigger; Face: flatter; Canine teeth: smaller; Chewing muscles: smaller.

Sahelanthropus tchadensis:

: ~6-7 mya, Chad: Oldest hominin fossil (Miocene); close to last common ancestor of humans and chimps.

Orrorin

~6 MYA Kenya (Miocene): ~6 MY old (Miocene); Kenya (2001); femur suggests walked upright

3

_ SPECIES LEFT AFRICA IN THE PAST 2 MILLION YEARS

~2.0M YA

Homo erectus evolved in Africa, some populations left Africa

~200K YA.

Homo heidelbergensis evolved in Africa, some populations left Africa

100K YA

Homo sapiens evolved in Africa 200K YA, some populations left Africa

homo erectus

1,890,000-143,000 YA: Jaw juts forward; Face not flat; Teeth small; Brow ridge; Used tools & fire; Lasted for 1.7 MY.

Homo heidelbergensis

700K to 200K YA; Evolved in Africa; Spread into Europe & Asia; Ancestor of neanderthals & modern humans;

African Branch

()what branch?) Stayed in Africa, speciated into H. sapiens

European Branch

Left Africa for Europe & Asia, then speciated into H. neanderthalensis; H. denisova

Homo neanderthalensis

~200,000 to 40,000 years ago.

humans, chimps, bonobos, gorillas, orangutans, and gibbons.

Have now sequenced the entire genomes of ______, _____, ______, _____, ______, and ______.

extinct species

Entire genome of ____ _____ sequenced by Svante Pääbo:

1-4%

____% DNA of whole genome of non-African humans is derived from Neanderthals

3-6%

___% DNA of whole genome of humans from Asia & Oceania is derived from H. denisova.

Tibetans

At one locus, _______ share more DNA with Denisovans than with Han Chinese.

0.5%

Little evidence of interbreeding between Neanderthals & Denisovans: they share only ___% DNA (Asia)

96.9%; 98.2%; 98.8%; 99%, 99.9%

% Human DNA Shared With Other Apes: Orangutan: ___% Gorilla ___%; Chimp ___%; Neanderthals ___%; Humans ___%

35; 1.2%; 3; 6250; 29%

Genetic Differences Between Humans & Chimps in 6 MY: total of __ million bases different (___%), __ m changes in coding DNA; _____ genes (__%) identical.

~600

____ genes & switches have either changed or been lost

(HAR1F)

Brain Development

FOXP2

Speech, Language

Fur Loss

KAPs keratin genes lost

36

Olfactory Receptors (fewer) (__ lost)

IL1 cytokines

Immunity genes different

MYH16 lost

Jaw muscles smaller

HAR2

Genes for thumbs, feet, ankles

Neanderthal DNA in humans

has had a subtle but significant impact on human traits. People with a Neanderthal version of a gene for hair, eye, skin color have associated medical conditions

Neanderthal

______ gene variants in humans may boost risk of depression, skin lesions, blood clots, & other disorders; whether an evening person or morning person; suffer from depression; a smoker, sunburn easily.

homo sapiens

we are all Africans: Big brain; Intelligence; Language; Technology; Curiosity; Scientific enlightenment

human/primate

Rich fossil, anatomical, embryological, chromosomal, genomic evidence for ______/______ relationships

7-6

Rich fossil evidence for emergence of Homo sapiens since divergence from chimps ~____ MYA

Rich genomic evidence

(whole genome sequencing) has enabled reconstruction of human evolution & early population movements, and has established interbreeding between species