1.6.2 Human Evolution: The Family Tree

Question 1

characteristics of the primate

Answer 1

1. opposable thumbs
2. nails instead of claws
3. long and limber arms for swinging from branches (brachiation)
4. forward facing eyes and depth perception
5. extended care of the young
   - earliest primates were arboreal insectivores who coexisted with dinosaurs

Question 2

note

Answer 2

• earliest primates were arboreal insectivores that coexisted with dinosaurs

Question 3

Around 55 million years ago, primates split into two major suborders

Answer 3

• Prosimii-a suborder of primates that includes lemurs and tarsiers
• Anthropoidea-a suborder of primates that includes gorillas and humans

Question 4

prosimii

Answer 4

• means “premonkey”
• this suborder diverged from the ancestral primates earlier in time than the monkeys. As members of the primate order, the prosimians share a certain set of
  characteristics with other primates. They have been evolving for at least 50 million years.
• The suborder includes modern representatives of lemurs, lorises, and tarsiers.

Question 5

anthropoids

Answer 5

• existed at least 40 million years ago. The anthropoid suborder includes New World monkeys, Old World monkeys, four genera of apes, and humans. Records
  indicate that New World monkeys and Old World monkeys have been evolving separately for millions of years.
• The 11 genera and 58 species of New World
  monkeys include the spider and howler monkeys.
• Members of the Old World monkeys include
  macaques, rhesus monkeys, baboons, and proboscis monkeys.

Question 6

apes

Answer 6

• The gibbon (genus Hylobates) is a lesser ape. The greater apes include apes and humans. The three genera of apes are Pongo (orangutans), Gorilla (gorillas), and Pan (chimpanzees).
• Several characteristics separate apes from
  monkeys. They include:
  • larger body size with proportionally long arms and short legs and no tails
  • primarily terrestrial living
  • high level of socialization
  • larger brains relative to body size

Question 7

phylogeny

Answer 7

• evolutionary history of a species or a group of related species

Question 8

Characteristics of the apes that separate them from the monkeys include

i. larger body size with proportionally long arms and short legs
ii. primarily arboreal
iii. highly socialized
iv. smaller brains relative to body size

Answer 8

• i, iii

Question 9

Approximately 55 million years ago, the order Primates split into two suborders, the Prosimii and Anthropoidea. Which one of the following is not included in the suborder Anthropoidea?

Answer 9

• lemurs

Question 10

Which of the following is not a characteristic of the primates?

Answer 10

• claws

Question 11

The earliest primates

Answer 11

• lived in trees.
• ate insects.
• coexisted with dinosaurs.

Question 12

Humans are most closely related to the

Answer 12

• African apes