ANP 120 - Module 11 - CH 10: What is a hominin?

For which reason is Australopithecus afarensis notable?

This species lived in a great diversity of habitats - Most other early hominins are associated with a narrower range of habitats.

A hominin is defined as having what two obligate behaviors? a. bipedal locomotion and nonhoning chewing b. speech and advanced cognition c. bipedal locomotion and speech d. nonhoning chewing and advanced cognition

a. bipedal locomotion and nonhoning chewing

Bipedalism's advantages over quadrupedalism include a. the ability to run faster. b. an increased ability to see greater distances and to carry food. c. the increased reproductive success. d. the ability to evade detection by standing very still.

b. an increased ability to see greater distances and to carry food.

Which trait is present in apes but absent in hominins? a. dental gap b. diastema c. mesial bridge d. gingival space

b. diastema

Repositioning of the gluteal muscles in bipeds helps them balance better during walking. true false

true

Match the features to the appropriate species.

Australopithecus anamensis: found near Lake Turkana - Many australopithecine fossils have been found in the vicinity of Lake Turkana, Kenya. most similar to pre-australopithecines - Australopithecus anamensis is the oldest known australopithecine and in many features is the most primitive. Australopithecus afarensis: associated with an extensive fossilized footprint track in Laetoli - Most Australopithecus afarensis fossils have been found in Ethiopia, but a few key remains, including the footprints, have been found at Laetoli, which is near Olduvai Gorge, in Tanzania. The short-statured individual, "Lucy," is a member of this species. - Lucy is the name given to the first nearly complete known skeleton of Australopithecus, because the song, "Lucy in the Sky with Diamonds," was being played in the field camp at the time of the discovery.

Using the graphic and the information provided below, identify this hominin by choosing the correct answer. may have descended from Au. afarensis large teeth and large face prominent sagittal crest South African found at Swartkrans, Kromdraai, and Drimolen Australopithecus robustusAustralopithecus sediba Australopithecus anamensisAustralopithecus afarensis

Australopithecus robustus - Note the sagittal crest, which is an apelike trait.

Identify whether the following features were reduced or increased in size between late australopithecines and early Homo. reduction in size increase in size

Brain: increase in size - Increase in brain size began around 2 million years ago but increased even more in the genus Homo. Advanced cognition is one of the elements that differentiates living apes from living humans today Face: reduction in size - Homo habilis's reduced face was due to the reduction of the chewing complex. Early Homo did not have as strong chewing muscles as australopithecines, indicating they did not eat as hard foods. Teeth: reduction in size - The reduction of teeth size goes along with other reductions in the skull.

Identify the statements that correctly describe the site of Bouri.

Correct Answer(s) : Bouri is located in the Middle Awash, Ethiopia. - Many important hominin sites are found in Ethiopia. Australopithecus garhi was found here. - Australopithecus garhi is only known from this location. Only indirect evidence of stone tool use in the form of cut marks and smashed bones has been found here. - Bouri has no chipped stone tools Incorrect Answer(s): Bouri is the only site where Australopithecus africanus is found. - Australopithecus africanus is found at many locations, but so far, not at Bouri.

This map shows the locations of several later australopithecine species, with some of the labels blanked out. Drag the name of each species to the appropriate blank to indicate where in Africa its fossil remains have been found. Australopithecus africanus Australopithecus aethiopicus Australopithecus afarensis Australopithecus anamensis

Hadar: Australopithecus afarensis - Australopithecus afarensis is found at many locations, and includes the famous skeleton known as "Lucy." West Turkana: Australopithecus aethiopicus - Australopithecus aethiopicus is one of the hyper-robust australopithecines, and some authorities place these species in the genus Parathropus. Australopithecus boisei is another eastern African species in this group. Do you know the name of the southern African species? Allia Bay: Australopithecus anamensis - Australopithecus anamensis dates to about 4 mya and was found within Allia Bay and Kanapoi, in, respectively, the eastern and southern ends of Lake Turkana, Kenya Taung: Australopithecus africanus - This hominin, found in South Africa, includes the Taung fossil, which is the first early hominin specimen found in Africa, reported by Raymond Dart in 1924.

Australopithecus anamensis is the oldest species currently known in the genus Australopithecus.

True Explanation: So far, Australopithecus anamensis fossils are the earliest in the genus, dating to 4 mya.

The foundational behavior of hominins was a. bipedalism. b. speech. c. hunting. d. tool use.

a. bipedalism.

Which of the following are features that differ between bipeds and quadrupeds? a. opposable big toe, length of the leg, shape of the spine, position of the foramen magnum b. opposable thumb, nails instead of claws, convergent eyes, longitudinal arch in the foot c. opposable thumb, shape of the spine, convergent eyes, longitudinal arch in the foot d. opposable big toe, length of the leg, convergent eyes, position of the foramen magnum

a. opposable big toe, length of the leg, shape of the spine, position of the foramen magnum

Hominins have canines that are a. small and nonprojecting, with no diastema. b. part of a honing complex. c. projecting and pointed, with a diastema. d. large and pointed, with no diastema.

a. small and nonprojecting, with no diastema.

The drawing represents three genera of pre-australopithecines. Match the key features to the correct species by dragging the terms to the appropriate place on the diagram. only the skull and teeth found, large brow ridge earliest clear evidence of bipedalism curved foot phalanges, nonhoning canine, thin enamel

answers in pic

Which of the following is an adaptive characteristic of bipedalism? a. flat feet b. longitudinal arch in the foot c. opposable thumb and big toe d. nails instead of claws

b. longitudinal arch in the foot

Based on the research of Philip Reno, early hominins show reduced sexual dimorphism, which is evidence for cooperation and likely for a. multimale grouping. b. pair-bonding. c. monogamy. d. multifamily grouping.

b. pair-bonding.

How is the temporalis muscle different in humans and in apes? a. The temporalis muscle enables better slicing motions in humans but not in apes. b. The temporalis muscle is more highly developed in humans. c. The temporalis muscle provides better crushing ability in apes but not in humans. d. The temporalis muscle is oriented vertically in humans and horizontally in apes.

d. The temporalis muscle is oriented vertically in humans and horizontally in apes.

Peter Rodman proposed that human evolution was linked to the __________ while Owen Lovejoy suggested the best explanation was __________. a. early emergence of a large brain; the later emergence of a large brain b. ability to carry food in order to provision family members; increased efficiency in walking as forests transformed to wooded environments c. ability to make and use stone tools; the loss of the diastema and evolution of thick enamel d. increased efficiency in walking as forests transformed to wooded environments; the ability to carry food in order to provision family members

d. increased efficiency in walking as forests transformed to wooded environments; the ability to carry food in order to provision family members

Identify the cranium of the species that most closely resembles the 3.7-million-year-old fossil that paleoanthropologist Ron Clarke referred to as Australipithicus prometheus, or "Little Foot."

see pic for answer

The human pelvis differs from Great Ape pelves in what way? A. Human and other ape pelves are not notably different B. Humans have a scaled down version of the ape pelvis, but otherwise it is unchanged C. Human pelves are shorter and directed towards the side of the body to help with things like weight support during bipedalism D. Human pelvises are much longer than apes, and more directed towards the back to help during bipedalism

C. Human pelves are shorter and directed towards the side of the body to help with things like weight support during bipedalism

Identify the statements that correctly describe Australopithecus platyops.

Correct Answer(s) : Australopithecus platyops had a relatively flat face. - Australopithecus platyops adds to our understanding of the diversity of the genus. Australopithecus platyops is associated with a woodland habitat. - So far, Australopithecus platyops has been found associated with a wooded habitat. Australopithecus platyops is one of the most poorly represented hominins. - Australopithecus platyops is known from a small number of fossils from one location. Incorrect Answer(s): Australopithecus platyops is one of the best-represented hominins. - Australopithecus platyops is known from a small number of fossils from one location.

Identify the dental traits that characterized the hyper-robust australopithecines.

Correct Answer(s) : large molars - Large molars were part of the enhanced chewing apparatus of these robust species. large lower jaw - The enlarged lower jaw was part of the enhanced chewing apparatus of the robust australopithecines. Incorrect Answer(s): large front teeth - The front teeth of these species were not enlarged as part of the enhanced chewing complex.

Identify the features of the pre-australopithecine Orrorin tugenensis.

Correct Answer(s): 6 mya - This is one of the earliest known hominins, though not the oldest. found in the Tugen hills - The Tugen Hills are south and west of Lake Turkana, Kenya. bipedal femurs, but no knee joint - Orrorin tugenensis is not as well represented as some other hominins, so we know less about its locomotion. Incorrect Answer(s): humanlike finger bones - This hominin has curved finger bones that are well adapted to locomotion in trees.

Identify the characteristics associated with Australopithecus afarensis.

Correct Answer(s): diverse diet indicated by diverse tooth wear - Australopithecus afarensis may have had the most diverse diet of the known australopithecines. nondivergent big toe - Researchers interpret Australopithecus afarensis's foot as close to that of modern humans. Incorrect Answer(s): flat face - Australopithecus afarensis had a very strongly projecting face, in contrast to some other australopithecines, which had a very flat face. human-sized brain - Major increase in brain size came much later in hominin evolution.

Identify the important features of the pre-australopithecine Sahelanthropus tchadensis.

Correct Answer(s): prominent brow ridges - The brow ridges of Sahelanthropus tchadensis are unusually large dates to 7-6 mya - Sahelanthropus tchadensis is the oldest known hominin. one of few hominin fossils found in Central Africa - Most hominins are found in East and Southern Africa. Sahelanthropus tchadensis is found in Central Africa. Incorrect Answer(s): nearly human-sized brain - Most early hominins have nonhuman ape-sized brains, and Sahelanthropus tchadensis is no exception.

Olduvai Gorge, located in the Great Rift Valley in Tanzania, is one of the most important sites for human evolutionary discoveries and is often referred to as the "cradle of humankind." Identify the statements that describe the site of Olduvai Gorge. - Olduvai Gorge contains layers of exposed geologic strata. - The limestone caves at Olduvai Gorge do not allow direct dating. - Raymond Dart was the paleoanthropologist behind the excavations at Olduvai Gorge. - Australopithecus boisei and Oldowan tools were found at Olduvai Gorge.

Describes Olduvai Gorge: Olduvai Gorge contains layers of exposed geologic strata. - Erosion and other geologic activities have exposed these strata, making fossils easier to discover than in other locations. Strata dating up to nearly 2 million years have been analyzed. Australopithecus boisei and Oldowan tools were found at Olduvai Gorge. - The Oldowan complex is named after Olduvai Gorge and demonstrates the first stone tool complex. Australopitcus boisei is the most famous fossil to come out of Olduvai Gorge. Does Not Describe Olduvai Gorge: The limestone caves at Olduvai Gorge do not allow direct dating. - Limestone caves characterize archaeological sites in South Africa. The strata at Olduvai Gorge are comprised of volcanic rock which can be radiometrically dated. The diagram shows a cross-section of these layers. Raymond Dart was the paleoanthropologist behind the excavations at Olduvai Gorge. - Raymond Dart worked in South Africa and was the discoverer of the "Taung child" and other significant Australopithecus fossils. Mary and Louis Leakey are the anthropologists who worked at Olduvai Gorge for decades. Explanation: Olduvai Gorge is one of many human evolution sites in Africa. This map shows the location of Olduvai Gorge within the context of other important sites.

Match each anatomical feature of Australopithecus sediba to the genus that usually shows the most similarity to that feature.

Homo: broad pelvis - The Au. sediba pelvis is broad and shaped like later species of Homo. noncurved phalanges - Some members of the genus Australopithecus have curved phalanges, but not Au. sediba. Noncurved phalanges suggests that Au. sediba was not adapted for arboreal movement. Australopithecus: small brain - The 420 cc brain is significantly smaller than any known species of Homo. long arms - This more primitive adaptation links Au. sediba to earlier australopithecines.

In this Anthropology at Work video, Dr. Brophy highlights a key aspect of research on human evolution and one that fascinates her the most. That is, the evolution of the genus ________ is so much more complex than we thought, and with every new fossil find comes _________ Homo Bovidae more questions than answers Pan more answers than questions

Homo; more questions than answers

Ardipithecus ramidus was a transitional species in many ways, with some features that were apelike, some humanlike, and others that were a mosaic of both. Place "apelike," "humanlike," or "mosaic" on the correct feature.

Top (skull) - humanlike - The teeth of Ardipithecus had short, nonprojecting canines and no honing complex. Middle (hand) - apelike - Curved fingers are an apelike adaptation for climbing and grasping. Bottom (foot) - mosaic - While Ardi's opposable big toe and elongated other toes were adapted for grasping, its feet were adapted for bipedality. This means that Ardi's feet are a mosaic feature.

Which of the following is an adaptive characteristic of bipedalism? a. narrow pelvis b. valgus knee c. flat feet d. C-shaped spine

b. valgus knee

How are molars used differently in humans than in apes? a. Human molars have more cusps than ape molars. b. Human molars have fewer cusps than ape molars. c. Human molars crush food more than ape molars. d. Human molars slice food more than ape molars.

c. Human molars crush food more than ape molars.

The earliest hominins probably lived in which kind of environment? a. open savanna grasslands b. arid, high-altitude uplands c. forested habitats d. dense tropical forest

c. forested habitats

Thick dental enamel in __________ helps with crushing food. a. apes b. pre-australopithecines c. hominins d. all primates

c. hominins

Which of the following is an adaptive characteristic of bipedalism? a. opposable thumb and big toe b. flat feet c. longitudinal arch in the foot d. nails instead of claws

c. longitudinal arch in the foot