Biology Final Exam

Gradualism

Evolution proceeds mainly by the accumulation of gradual changes

Evolution

the change in inherited characteristics of populations over many generations

Natural Selection

a mechanism of evolution where organisms with the best-suited traits are more likely to reproduce, passes advantageous traits to their offspring

Artificial Selection

Modificaiton by humans by selecting and breeding individuals with desired traits

Adaptive Radiation

a rapid increase in the number of species with a common ancestor, characterized by great ecological diversity.

Homolgy

The similarity in structure, position, or origin among different species due to common ancestry, despite differences in function.

Homologous Structures

Anatomical resemblances that represent variations on a structural theme present in a common ancestor

Derived State

A trait that has evolved from an ancestral trait and is distinct to certain taxa.

Ancestral State

A trait or characteristic that is inherited from a distant ancestor and is present in the common lineage of a group.

Cladisitcs

A method of classifying organisms based on common ancestry and shared derived characteristics to construct evolutionary trees.

Phenetics

A classification method that groups organisms based on overall similarity, often using quantitative measures of morphological traits.

Population

A group of individuals of the same species that live in a specific area and interbreed, sharing a common gene pool.

Phylogeny

The evolutionary history and relationship among species or groups of organisms.

Systematics

Focused on classifying and organizing organisms, understanding evolutionary relationships, and describing their diverse characteristics

Convergent Evolution

Process where unrelated or distant organisms evolve similar traits in response to similar ecological pressure

Taxonomy

The science of classifying a living or extinct organism into a group

What factors drive population change (microevolution)?

Population size, genetic drift, mutation, natural selection, and gene flow.

What factor(s) in populations guarantees natural selection in any environement?

Variation among individuals and heritability of traits.

How does genetics impact natural selection?

Genetics provides the heritable variation necessary for natural selection to occur, allowing advantageous traits to be passed on to future generations.

Will natural selection ever stop? why or why not?

Natural selection will not stop as long as there is variation in traits among individuals in a population. It is an ongoing process driven by changing environments and the need for adaptation.

Can there every be a “perfect” species?

No, a perfect species cannot exist due to the ever-changing nature of the environment and the continuous evolution of traits within populations.

Provide at least three examples supporting the theory of evolution

Examples include the fossil record demonstrating gradual changes, observable natural selection in finch beak sizes, and molecular evidence showing genetic similarities among species.

Provide a simple arugment that may refute the theory of evolution

One argument against the theory of evolution is the presence of complex structures that seem to be irreducibly complex, meaning they cannot function if any part is removed, suggesting they could not have evolved gradually.

Why do molecular homologies correspond with anatomical ones?

Molecular homologies correspond with anatomical ones because they reflect shared genetic heritage, indicating that organisms with similar DNA sequences likely share a common ancestor.

Why can you infer regarding the habitats between species that display convergent evolution?

You can infer that species displaying convergent evolution have adapted to similar environmental pressures or ecological niches, resulting in analogous traits despite having different evolutionary histories.

with all the evidence for evolution, why is it still considered a theory?

It is still considered a theory because in science, a theory represents the best explanation based on extensive evidence, but it remains open to testing, refinement, and potential falsification as new information emerges.

Difference between micro and macro evolution

Microevolution refers to small-scale changes within a species, such as shifts in allele frequencies, while macroevolution encompasses larger-scale changes that occur over long periods, leading to the emergence of new species and higher taxa.

How does evolutionary theory impact modern medicine?

Evolutionary theory impacts modern medicine by informing our understanding of disease evolution, antibiotic resistance, and the development of vaccines, helping to create more effective treatment strategies.

Compare benefits and detriments of cladistics vs. phenetics

Cladistics is beneficial for depicting evolutionary relationships based on common ancestry, while phenetics focuses on overall similarity and can sometimes mislead phylogenetic accuracy. Cladistics may exclude unrelated species based on a shared trait, whereas phenetics might group dissimilar organisms.

Why do you think humans have never observed one species evolving into another

Largely due to the amount of time it takes to see a noticeable change in any type of evolution in a creature, takes up too much time for our lifespans to ever realize that change had ever happened in the first place.

Hereditary Variation

The differences between individuals that are passed down from parents through their genes

Naturally Varying by Heredity

Genetic differences between individuals within a species. Genetic variation is a key driver of evolution through natural selection

Difference between derived and ancestral traits

Derived traits evolved from ancestral ones; ancestral traits are inherited from a distant ancestor and present in the common lineage of a group.