Exam Reveiw Evolution Flashcards
define evolution
Evolution: The process by which different kinds of living organisms develop and diversify from earlier forms during the history of the Earth.
define speciation
Speciation: The formation of new and distinct species in the course of evolution.
define niche
The role or function of an organism or species within an ecosystem, including its habitat, resource use, and interactions with other organisms.
define mutation
A change in the DNA sequence of an organism, which can lead to new variations within a species.
define selective pressure
Environmental factors that influence the survival and reproduction of individuals within a population, leading to natural selection.
define adaptive radiation
The diversification of a group of organisms into forms filling different ecological niches.
what are the types of evolution
Divergent Evolution: When two species evolve in different directions from a common point.
Convergent Evolution: When species from different ancestral origins evolve similar traits.
Parallel Evolution: When two related species evolve in similar ways over time, often in response to similar environmental challenges.
What are the lines of evidence for evolution?
Fossil Record: Shows changes in species over time.
Comparative Anatomy: Similar structures (homologous structures) in different species.
Embryology: Similar embryonic development in different species.
Molecular Biology: DNA and genetic similarities among different species.
Biogeography: Distribution of species around the world supports patterns of evolution.
What are the three types of selection and sketch a graph for each?
Stabilizing Selection: Favors the average phenotype.
Graph: High peak in the center of the curve.
Directional Selection: Favors one extreme phenotype.
Graph: Shift of the peak towards one end of the curve.
Disruptive Selection: Favors both extreme phenotypes.
Graph: Two peaks, one at each end of the curve.
what contributions did charles darwin make
Charles Darwin: Proposed natural selection as a mechanism for evolution in “On the Origin of Species”.
what contributions did jean baptiste lamarck make
Jean-Baptiste Lamarck: Suggested that organisms could pass on traits acquired during their lifetime to their offspring.
what contributions did Georges-Louis Leclerc, Comte de Buffon make
Georges-Louis Leclerc, Comte de Buffon: Proposed that species could change over time and suggested the idea of common ancestry.
what contributins did charles lyell make
Charles Lyell: His work on uniformitarianism in geology influenced Darwin’s thinking about gradual change over time.
what contributions did georges cuvier make
Georges Cuvier: Developed the theory of catastrophism and established extinction as a fact.
Describe the differences between artificial and natural selection.
Artificial Selection: Human intervention in animal or plant reproduction to ensure certain traits are represented in future generations.
Natural Selection: The process by which organisms better adapted to their environment tend to survive and produce more offspring.
what is needed for natural selection to occur
Requirements for Natural Selection:
Variation: Differences in traits within a population.
Heritability: Traits must be heritable.
Differential Reproduction: Some traits must confer a reproductive advantage.
Overproduction: More offspring are produced than can survive.
Give three examples of homologous features
Homologous Features:
Forelimbs of mammals (human arm, bat wing, whale fin).
Vertebrate eyes.
Leaves of different plant species.
Give three examples of analogous features
Vestigial Features:
Human appendix.
Pelvic bones in whales.
Wings in flightless birds.
Give three examples of vestigial features
Analogous Features:
Wings of insects and birds.
Flippers of dolphins and penguins.
Eyes of octopus and mammals.
what is the bottleneck effect
A sharp reduction in the size of a population due to environmental events or human activities.
what is genetic drift
Random changes in allele frequencies in a population, particularly in small populations.
what is the founders effect
When a new population is started by a small number of individuals, leading to reduced genetic variation.
Distinguish between microevolution and macroevolution.
Microevolution: Small-scale evolutionary changes within a species or population.
Macroevolution: Large-scale evolutionary changes that result in the formation of new species.
Distinguish between prezygotic and postzygotic mechanisms
Prezygotic Mechanisms: Prevent mating or fertilization between species (e.g., temporal isolation, behavioral isolation, mechanical isolation).
Postzygotic Mechanisms: Occur after fertilization and reduce the viability or reproductive capacity of hybrid offspring (e.g., hybrid inviability, hybrid sterility).
