Question 1

The fossil record is biased because preservation is selective.

Accepted Answer

The fossil record is biased because only a small fraction of organisms that have ever lived have been preserved as fossils, and preservation is selective based on factors such as the environment, the size and hardiness of the organism, and the likelihood of being buried and preserved.

Question 2

The law of stratigraphy states that the oldest fossils will be found at the bottom of a layer of rock.

Accepted Answer

The law of stratigraphy, also known as the law of superposition, states that in an undisturbed sequence of sedimentary rock layers, the youngest layers are on top and the oldest are on the bottom. Therefore, the oldest fossils will be found at the bottom of a layer of rock.

Question 3

Genetic drift occurs to some degree in all populations of finite size.

Accepted Answer

Genetic drift is a random fluctuation in the frequency of alleles in a population that occurs due to chance events. It is more pronounced in smaller populations, where chance events have a greater impact on the overall composition of the gene pool. As all populations have a finite size, genetic drift occurs to some degree in all populations.

Question 4

Phenotypic gradualism is generally accepted as fact although phyletic gradualism is still highly controversial.

Accepted Answer

Phenotypic gradualism and phyletic gradualism both refer to the concept of gradual evolutionary changes over time. The controversy or acceptance of these ideas is not distinctly separated as the statement suggests; both concepts are part of the broader discussion on the pace and mode of evolution, with debates often focusing on the evidence for gradual versus punctuated evolutionary changes.

Question 5

Recurring mutation is the ultimate source of variation in natural populations,but it is usually not sufficient by itself to promote significant evolutionary change.

Accepted Answer

Recurring mutation is an important source of variation in natural populations. However, for significant evolutionary change to occur, other processes such as natural selection, genetic drift, gene flow, and genetic recombination must also be involved.

Question 6

Fighting prowess as characterized by unbridled aggression and violence in a competitive world is regarded as the only means of leading to fitness and reproductive advantage.

Accepted Answer

This statement is a misconception that has been debunked by scientific research. While physical fitness and strength can provide advantages in survival and reproduction, aggression and violence are not necessary for this. In fact, species that rely on cooperation and social bonds often outcompete those that prioritize aggression. Additionally, in human societies, non-violent traits such as intelligence and creativity have played a significant role in promoting survival and reproductive success.

Question 7

The main premise underlying Darwinian evolution is that the living world is neither constant nor perpetually cycling,but is always changing.

Accepted Answer

The main premise of Darwinian evolution is that the living world is always changing through the process of natural selection, and is not constant or perpetually cycling. This premise forms the basis for understanding how species adapt and evolve over time through the mechanisms of variation, inheritance, and differential survival and reproduction.

Question 8

In many human populations,genetically recessive traits may be very common.

Accepted Answer

This is true. Even though individuals may carry the recessive gene, it may not be expressed unless both parents contribute the recessive gene to the offspring. This can lead to a high prevalence of recessive traits in a population.

Question 9

Darwin's evolutionary theory differs from Lamarck's in being a variational rather than transformational theory.

Accepted Answer

Darwin's theory proposes that traits in a population vary and that some variations may provide a selective advantage, leading to the survival and reproduction of individuals with these advantageous traits. In contrast, Lamarck's theory suggested that individuals can acquire characteristics throughout their lifetime and pass them on to their offspring, leading to a transformation of species over time. Thus, Darwin's theory is variational in nature, while Lamarck's theory is transformational.

Question 10

Geographic barriers and reproductive barriers are basically the same thing because geographic barriers will separate two populations,prevent gene exchange,and are a precondition for speciation.

Accepted Answer

Geographic barriers and reproductive barriers are not the same thing. While geographic barriers physically separate populations, reproductive barriers refer to mechanisms that prevent interbreeding between populations even if they are in the same geographic area. Reproductive barriers can arise due to differences in mating behaviors, anatomy, or genetics, and contribute to speciation.

Question 11

The most common mode of speciation in animals is sympatric speciation.

Accepted Answer

The most common mode of speciation in animals is actually allopatric speciation, which occurs when a population is geographically isolated and evolves separately from the original population. Sympatric speciation, where speciation occurs within the same geographic area, is relatively rare in animals but may occur through mechanisms such as polyploidy or disruptive selection.

Question 12

According to the Hardy-Weinberg Law,the frequency of each allele remains constant generation after generation in a freely interbreeding,sexually reproducing,large population that experiences natural selection.

Accepted Answer

The Hardy-Weinberg Law states that allele frequencies remain constant in a population only if there is no natural selection, mutation, migration, genetic drift, or non-random mating.

Question 13

The Precambrian era of geological time represents 85% of all geological time and contains most of the known fossils of large animals.

Accepted Answer

The Precambrian era represents 85% of all geological time, but it is known for the absence of large animal fossils. The majority of fossils found from this era are microorganisms and simple, single-celled organisms.

Question 14

The most direct evidence for Darwin's theory of perpetual change is the fossil record.

Accepted Answer

The fossil record provides direct evidence for Darwin's theory of perpetual change, also known as evolution, through the observation of changes in the types and characteristics of organisms over time. These changes reflect the process of natural selection and support the idea that species evolve and adapt over time in response to changing environmental conditions.

Question 15

Haeckel's theory that ontogeny recapitulates phylogeny suggests that early development features were more widely shared among different animal groups than later features.

Accepted Answer

Haeckel's theory suggests that during embryonic development, an organism goes through stages that reflect its evolutionary history, with early stages representing more ancient ancestors and later stages reflecting more recent evolutionary changes. Therefore, according to this theory, early developmental features were more widely shared among different animal groups than later features.

Question 16

The theory of evolution by natural selection was proposed by

Accepted Answer

The theory of evolution by natural selection was proposed by both Darwin and Wallace independently. Darwin had been working on his ideas for many years but was spurred into publishing them when he received a letter from Wallace outlining similar ideas. While other scientists, such as Malthus and Lamarck, had influenced their thinking, Darwin and Wallace are the two primary individuals credited with proposing the theory of evolution by natural selection.

Question 17

The possible use of appendages as sails in aquatic insects that may have incidentally evolved into wings supports an evolutionary position.
Multiple Choice Questions

Accepted Answer

The statement supports the evolutionary position that wings evolved from appendages, suggesting a common ancestor from which both appendages and wings evolved.

Question 18

Inbreeding tends to decrease the probability that rare recessive traits will be seen in the following population.

Accepted Answer

Inbreeding actually increases the probability of rare recessive traits being expressed, as there is a higher chance of individuals carrying the same recessive gene mating and passing it onto their offspring. This can lead to higher frequency of genetic disorders and reduced fitness.

Question 19

The evolutionary history of horses from the Eocene to the present shows the progressive evolutionary change of a single species by natural selection.

Accepted Answer

The evolutionary history of horses actually involves the gradual appearance and disappearance of many different species over time, each adapted to different environmental conditions, rather than a linear progression of a single species. While there is a general trend towards larger body size and more efficient running abilities, this is not a straightforward process and there are many branches and dead ends in the horse family tree.

Question 20

Macroevolutionary studies address large-scale changes in the frequencies of different allelic forms of genes in natural populations.

Accepted Answer

Macroevolutionary studies focus on the processes that lead to the emergence of new species and the large-scale evolutionary changes above the species level, not on changes in allelic frequencies within populations, which is the focus of microevolution.

Quiz 1: Science of Zoology and Evolution of Animal Diversity