Microevolutionary processes #8 Flashcards
What is adaptation in the context of evolution?
Adaptation refers to special features that enhance survival or reproduction in a species’ environment.
Give an example of adaptation in unrelated plants in arid environments.
Unrelated plants in arid environments have adaptations to reduce water loss.
What is convergent evolution?
Convergent evolution is when a feature evolves independently in many lineages due to similar selective pressure.
Give an example of convergent evolution.
The body form of fishes is adapted for different modes of swimming, where fish in the open ocean have a slender body while fish in small spaces have deep bodies.
How do adaptations evolve?
Adaptations evolve by natural selection, which is a non-directed, goal-less process. Over time, natural selection shapes the information in DNA, resulting in changes in characteristics that enhance fitness relative to alternate states.
What is pre-adaptation?
Pre-adaptation refers to features that already occur in organisms and get co-opted towards new functions.
Give an example of pre-adaptation.
The kea bill evolved for cracking seeds.
What are non-adaptive reasons for traits?
Non-adaptive reasons for traits refer to factors other than natural selection or adaptation that can lead to the appearance of certain traits in a population. Examples include genetic drift, historical and developmental constraints, neutral mutations, and genetic hitchhiking.
How do we know if a trait is adaptive?
We can use several methods to determine if a trait is adaptive, including experiments, comparative method, and looking at the phylogenetic history of the trait.
Are all traits adaptations?
No, not all traits are adaptations. Some traits are consequences of chemistry or physics, while others are a result of random genetic drift or correlated with a trait under selection.
What are adaptive radiations?
Adaptive radiations refer to the process of natural selection producing species-rich groups of related organisms over long time frames.
Is evolution too slow to observe?
Evolution was historically considered too slow to observe, but there are now many examples of rapid adaptive evolution, often via standing variation.
What are some examples of rapid adaptive evolution?
Examples of rapid adaptive evolution include morphological, physiological, and behavioral changes.
What are the implications of adaptive evolution in the Anthropocene?
Adaptive evolution in the Anthropocene may have significant implications, such as the rapid evolution of arthropod pests to different classes of insecticides.
What is natural selection?
Natural selection is the differential survival and reproduction of individuals due to differences in their phenotype, resulting in the increase of successful alleles in the gene pool over time.
