Question 1

What does the positioning of the toe indicated by the arrow in this figure suggest about the owner of this fossil hominid foot?

Accepted Answer

The positioning of the toe indicated by the arrow suggests that the owner of this fossil hominid foot was adapted for walking upright on two feet, as the big toe is aligned with the other toes rather than being opposable like in primates adapted for tree-swinging. However, there is no clear evidence about how much time this hominid spent in trees.

Question 2

The phylum Chordata includes several subgroups of organisms.To which of these subgroups would humans belong?

Accepted Answer

Humans belong to the subgroup of Chordata called Vertebrates, which includes animals with a backbone, such as fish, birds, and mammals.

Question 3

You are relaxing on the veranda of your beachfront rental on the Gulf of Mexico when you notice a small (about 5 inches long),green quadruped clinging to the ceiling.As it begins to run down the wall,you catch it and notice that it is covered with dry scales,has a long tail,and specialized toe pads that allow it to stick to surfaces.This animal most likely belongs to which class?

Accepted Answer

The characteristics mentioned, such as dry scales, specialized toe pads, and a long tail, are typical of reptiles. Mammals do not have dry scales or toe pads, while amphibians have smooth skin instead of scales and do not have specialized toe pads for clinging. Osteichthyes refers to bony fish, which do not have the adaptations mentioned.

Question 4

Which of the following is NOT an advantage of bipedalism in hominins?

Accepted Answer

Standing on two feet does not make it easier to climb trees. In fact, bipedalism may have hindered climbing ability as it requires balance and stability on two legs rather than four.

Question 5

The development of upright posture in hominins is likely

Accepted Answer

Upright posture would have been advantageous for hominins living on the ground as it would have allowed them to see over tall grasses and spot predators or prey. It also would have freed their hands for tool use and other activities.

Question 6

Which of the following could NOT be used to describe humans?

Accepted Answer

Humans are not marsupials. Marsupials are a group of mammals that have a pouch in which they carry and nurse their young. Humans do not have a pouch and do not nurse their young in this way.

Question 7

Fossilized foot bones show that some hominids living between 3 and 3.5 mya walked upright but had partially opposable big toes.This suggests that

Accepted Answer

The fossilized foot bones suggest that the shift to bipedalism was not sudden and complete, and that the earliest bipedal hominins may have also spent some time in the trees for shelter or to find food. The partially opposable big toe may have helped these hominids to grip and climb trees.

Question 8

Which of the following is NOT a feature of hominins that distinguishes them from other hominids?

Accepted Answer

Hominins are characterized by bipedal walking, upright posture, and a relatively flat face. An opposable big toe is not a distinguishing feature of hominins; it is more associated with non-human primates that use their feet for grasping.

Question 9

Which of the following categories of the Linnaean hierarchy would include the broadest range of related organisms?

Accepted Answer

Phylum is a category in the Linnaean hierarchy that includes a broad range of related organisms, such as all animals with a spinal cord (Chordata) or all plants with seeds (Spermatophyta). Species, on the other hand, only includes organisms that can interbreed and produce viable offspring. Therefore, phylum would be the best choice for the question.

Question 10

Which of the following groupings of animals are most closely related to each other?

Accepted Answer

Lemurs, chimps, and humans are all primates and share a common ancestor.

Question 11

All primates have opposable thumbs.This means the thumbs

Accepted Answer

Opposable thumbs refer to the ability to touch the thumb to each of the other fingers on the same hand, allowing for a better grip and manipulation of objects.

Question 12

The correct two-word Latin,scientific name,for modern humans is

Accepted Answer

The correct two-word Latin, scientific name for modern humans is Homo sapiens. It is capitalized and italicized, with the first word (Homo) representing the genus and the second word (sapiens) representing the species. The other options represent extinct hominid species, with Homo neanderthalensis referring to Neanderthals.

Question 13

Which of the following anatomical changes was NOT likely a contributor to the development of full bipedalism in hominins?

Accepted Answer

Having no arch in the foot would not have been a contributor to the development of full bipedalism in hominins. In fact, having an arch in the foot helps with shock absorption and stability while walking upright on two legs. Therefore, this anatomical change would have likely hindered rather than helped the development of bipedalism. The restructuring of the pelvis, loss of opposable big toes, and change in the angle of knee joints that support body weight all would have been necessary adaptations for efficient bipedalism.

Question 14

You are on an archaeological dig in Africa when you find a collection of stone tools along with several skeletons in a cave.These bipedal skeletons date to about 3.5 million years ago and show no evidence of a partially opposable toe.Measurements indicate the brains would have been a little less than a third of the volume of modern humans.The teeth found on these skeletons look more like those of an ape than those of a human.Your skeletal discovery is most likely which of the following?

Accepted Answer

Australopithecus afarensis lived around 3.9 to 2.9 million years ago, were bipedal, had small brain sizes, and their teeth were more ape-like, fitting the description given.

Question 15

You are camping in the south central United States when one evening you happen across an animal with several "armored" plates covering its back and shoulders.The plates are bony and separated by thin bands of flexible skin.The belly of this short-legged quadruped is covered with skin and soft fur.You also notice four young ones scurrying along with the adult.This animal most likely belongs to which class?

Accepted Answer

The description matches an armadillo, which is a mammal. Mammals are characterized by having fur or hair and, in most cases, giving live birth. Armadillos are known for their bony armor and are native to the Americas, including the south central United States.

Question 16

The first vertebrates to evolve lacked jaws and had skeletons made from a strong flexible tissue called cartilage.The lamprey is a modern example of this ancient group of vertebrates known as

Accepted Answer

The statement mentions that the ancient group of vertebrates being referred to lacked jaws and had cartilage skeletons. This description matches that of jawless fishes, also known as agnathans. Therefore, the best choice is D) jawless fishes.

Question 17

According to this evolutionary tree,when did hominins branch away from the other apes?

Accepted Answer

The answer of According to this evolutionary tree,when did hominins...

Question 18

Which of the following adaptations was NOT required to facilitate the evolution of animal life on land?

Accepted Answer

A fully cartilaginous skeleton is not a necessary adaptation for animals to live on land. While some animals with cartilage-based skeletons, such as sharks, can survive on land for short periods of time, a fully cartilaginous skeleton is not required for the long-term survival and adaptation of animals on land. Water-conserving excretory systems, amniotic eggs, and waterproof skin, on the other hand, are essential adaptations that enable animals to live and reproduce away from water sources.

Question 19

Which of the following traits was likely deleterious for early hominins?

Accepted Answer

An opposable big toe would have been deleterious for early hominins as it would hinder efficient bipedal walking, which was crucial for survival and adaptation in their environment.

Question 20

Which of the following categories of the Linnaean hierarchy would include the most closely related organisms?

Accepted Answer

Organisms within the same genus share a more recent common ancestor and have more similar characteristics than organisms within the same family, class, or order.

Quiz 14: Human Evolution