32. Vertebrates

Analysis of DNA from a variety of sources has led most researchers to agree that __________.

What was the earliest hominin to have an enlarged brain (relative to body size)?

__________ arose very early in hominid evolution; __________ evolved more recently.

Which of the following correctly lists probable ancestors of modern humans from the earliest to the most recent?

Which of the following traits distinguishes hominins from other apes?

Included among the extant groups of apes are __________.

All species of New World monkeys are __________.

Humans and lorises share many traits that probably evolved in our early primate ancestors; one such trait is __________.

Primates are distinguished from other mammals by __________.

In the primate phylogenetic tree below, fill in groups (a)–(e). Of the groups, which are anthropoids and which are apes? a. b. c. d. e.

Most species of hominins are known only from Africa. Which species have been found in other parts of the world as well? a. early Homo—H. habilis and H. ergaster b. H. erectus, H. neanderthalensis, and H. floresiensis c. gracile australopithecines d. robust australopithecines

Fossils suggest that the first major trait distinguishing hominins from other primates was a. a larger brain. b. erect posture. c. forward-facing eyes with depth perception. d. tool making.

Which of the following correctly lists possible ancestors of humans from the oldest to the most recent? a. Homo erectus, Australopithecus, Homo habilis b. Australopithecus, Homo habilis, Homo erectus c. Australopithecus, Homo erectus, Homo habilis d. Homo ergaster, Homo erectus, Homo neanderthalensis

Which of these is not a member of the anthropoids? a. chimpanzee b. tarsier c. human d. New World monkey

Studies of DNA support which of the following? a. Members of the group called australopiths were the first to migrate from Africa. b. Homo sapiens originated in Africa. c. Sahelanthropus was the earliest hominin. d. Chimpanzees are more similar to gorillas and orangutans than to humans.

The earliest members of the genus Homo a. had a larger brain compared to other hominins. b. probably hunted dinosaurs. c. lived about 4 million years ago. d. were the first hominins to be bipedal.

One of the misconceptions about human evolution is expressed in the question 'If chimpanzees were our ancestors, then why do chimpanzees still exist?' Use Figure 19.10A to explain the answer.

What adaptations inherited from our primate ancestors enable humans to make and use tools?

Summarize the hypotheses that explain variation in human skin color as adaptations to variation in UV radiation.

Explain some of the reasons why the human species has been able to expand in number and distribution to a greater extent than most other animals.

Anthropologists are interested in locating areas in Africa where fossils 4–8 million years old might be found. Why?

SCIENTIFIC THINKING By measuring the fossil remains of Homo floresiensis, scientists have estimated its weight to be around 32.5 kg and its brain volume to be roughly 420 cm3. Plot these values on the graph in Figure 19.13A. Which hominin has the most similar relationship of brain volume to body mass? Does this information support the hypothesis that H. floresiensis is a dwarf form of H. erectus, or an alternative hypothesis? Explain.