Question 1

What is a likely result of a mass extinction?

Accepted Answer

A mass extinction event can create a "vacuum" of ecological niches, where surviving species can evolve to fill the empty niche space. This can lead to radiation of surviving groups and diversification of species.

Answer: B
 In a mass extinction event, species that are poorly adapted to changing conditions are more likely to go extinct. This can reduce the amount of non-beneficial traits in the gene pool, leading to a more fit population overall.

Answer: D
 Mass extinction events can create periods of instability where species are more likely to go extinct, reducing the amount of genetic diversity in the gene pool. This can lead to a decrease in the rate of new mutations. It is important to note that this is not a universal outcome and may depend on the specific circumstances of the extinction event.

Question 2

When did the first land plants appear?

Accepted Answer

The first land plants appeared during the Ordovician period, which occurred approximately 485 to 444 million years ago.

Question 3

What genes control the overall body plan of animals?

Accepted Answer

Hox genes play a major role in controlling the overall body plan of animals by regulating the development of different body segments along the anterior-posterior axis. They are also involved in the specification of specific organs and tissues within the body. Pax genes, homeobox genes, and homeodomain genes are also involved in various aspects of animal development, but they do not have as prominent a role in controlling the overall body plan.

Question 4

A single seed lands on one of a group of isolated islands. Several million years later, its descendants have evolved into a number of new species on the different islands, representing a variety of trees, shrubs, and vines. What is this an example of at that point in time?

Accepted Answer

This scenario describes adaptive radiation, which is a process in which a single species evolves into multiple new species to adapt to different environmental conditions. The different species evolve from a common ancestor and each occupy a distinctive niche in their respective habitats on the different islands.

Question 5

Why were there not that many fossils until teeth and bones appeared in fossil finds?

Accepted Answer

Hard tissues such as teeth and bones have a higher likelihood of being preserved through mineral fossilization compared to soft tissues which are more likely to be fossilized as moulds. Therefore, the appearance of teeth and bones in fossil finds increases the chances of finding well-preserved fossils.

Question 6

Recent research on fossil records of lambeosaurines implies the function of their bony crest. Which of the following is its most probable function?

Accepted Answer

Recent research on the fossil record of lambeosaurines suggests that their bony crests were resonating chambers that amplified and modified vocalizations, allowing for honking calls to be produced. This is supported by studies showing that the size and shape of the crest vary among species, potentially influencing the quality and frequency of sounds produced.

Question 7

What were the first organisms to move onto land?

Accepted Answer

Plants accompanied with fungi were among the first organisms to colonize land, as fungi helped plants absorb nutrients from the soil.

Question 8

Which of the following is an example of analogous characters?

Accepted Answer

Analogous characters refer to traits that are similar because they serve the same function, not because they were inherited from a common ancestor. The sweet potato (which grows underground as a root) and the potato (a tuber, also underground) serve similar functions as food storage organs but evolved independently in different plant families, making them analogous.

Question 9

Which of the following plants are considered the oldest of the vascular plants?

Accepted Answer

The treelike lycopsids or scale trees are considered the oldest of the vascular plants, dating back to the Devonian period over 380 million years ago. While liverworts and mosses are also ancient plant groups, they are non-vascular and lack true roots, stems, and leaves. While tree ferns are vascular, they first appeared during the late Carboniferous period, which is much later than the treelike lycopsids.

Question 10

Which of the following present characters that systematists use to develop phylogenies?

Accepted Answer

Systematists use a combination of morphological features, behavioral traits, and molecular data (including sequences of nucleic acids and proteins) to develop phylogenies. Therefore, option B - morphological features, behavioral traits, sequence of nucleic acids, and proteins - is the best choice.

Question 11

What does the Cretaceous-Paleogene event refer to?

Accepted Answer

The Cretaceous-Paleogene event refers to an event in which an asteroid impact caused a mass extinction event, resulting in the extinction of most of the dinosaurs and 75% of all species.

Question 12

Which of the following information provides clues to the origin of cetaceans?

Accepted Answer

Isotopic analysis of the teeth of Indohyus provided evidence that it lived in freshwater environments similar to the habitats of early cetaceans. This suggests that cetaceans may have evolved from terrestrial ancestors that lived in freshwater habitats, rather than marine environments.

Question 13

Which insects belong to the group of hemimetabolous insects?

Accepted Answer

Hemimetabolous insects undergo incomplete metamorphosis, which means they do not have a pupal stage. Instead, they hatch from eggs and resemble miniature adults, undergoing a series of molts to reach their final form. Examples of hemimetabolous insects include cockroaches and dragonflies. Beetles belong to the group of holometabolous insects, which undergo complete metamorphosis with distinct larval, pupal, and adult stages. Moths and ants also belong to the group of holometabolous insects.

Question 14

What are the genes that determine where appendages will develop on the animal's body called?

Accepted Answer

The genes that determine where appendages will develop on the animal's body are called Hox genes. These genes play a crucial role in the proper development and segmentation of an animal's body plan. Mutations in Hox genes can result in abnormal development and anatomical structures.

Question 15

A single pregnant female parakeet arrives in Hawaii early in its history. After millions of years, her descendants have successfully adapted to a variety of foods and habitats. What is this is the result of?

Accepted Answer

This is an example of adaptive radiation, where a single ancestral species diversifies into multiple descendant species, each adapted to a specific niche or habitat. The parakeet's descendants have adapted to different foods and habitats in Hawaii over millions of years, resulting in a variety of species. Genetic drift is a random process that can lead to changes in allele frequencies in a population, but it is unlikely to result in the diversity of species seen in this scenario. Allopatric speciation involves the geographic isolation of populations, which can lead to the evolution of new species, but there is no indication that this occurred in the parakeet's case. Similarly, sympatric speciation involves the evolution of new species within the same geographic area, which is not the case here.

Question 16

What is adaptive radiation?

Accepted Answer

Adaptive radiation is the process by which a single species diversifies into several different species, each occupying a distinct ecological niche. This process often occurs when a common ancestor colonizes a new environment with many available ecological niches that can be exploited. Over time, natural selection favors the evolution of traits that allow different populations to exploit different resources and occupy different niches, leading to the development of many new species from a single common ancestor.

Question 17

To which lineage do sea cows belong?

Accepted Answer

Sea cows, or sirenians, belong to an African lineage of mammals that also includes elephants, as they share a common ancestor.

Question 18

Which insects belong to the group of holometabolous insects?

Accepted Answer

Holometabolous insects undergo complete metamorphosis, which includes four stages: egg, larva, pupa, and adult. Beetles, moths, ants, and flies all undergo complete metamorphosis, making them holometabolous. Dragonflies and cockroaches do not undergo complete metamorphosis.

Question 19

How far back do the fossil records of whales and toothed whales extend?

Accepted Answer

Fossil records of whales and toothed whales extend back to the Eocene epoch, which began around 56 million years ago. Therefore, the best choice is C, which states that the fossil records extend back more than 50 million years.

Question 20

What suggests that the earliest movement of animals onto land occurred as short visits?

Accepted Answer

The movement of modern fishes, annelids, molluscs, and arthropods onto land suggests that the earliest movement of animals onto land occurred as short visits. This is because these animals are all able to survive on land for short periods of time, but they cannot reproduce on land. This suggests that the earliest animals to move onto land were not able to establish permanent populations on land, and that they only visited land for short periods of time.

Quiz 20: Understanding the History of Life on Earth