AP bio unit 7 speciation and extinction

Speciation

process where new species arise

microevolution

Change in genetic makeup of a populatoion from generation to generation.

• single gene pool

Macroevolution

evolutionary change above the species level

• appearance of feathers

What is a species

a group of populations who members can interbreed and produce fertile offsprings

What is reproductive isolation?

Collection of evolutionary mechanisms, behaviors, and physiological processes critical for speciation, which prevent members of different species from interbreeding.

What are prezygotic barriers?

prevent mating or inhibit fertilization

habitat isolation

Live in the same geographic area but not in same habitat ehavB

Behavioral isolation

some species use certain signals or types of behaviors to attract mates that are unique to their species

Temporal isolation

species may breed at different times of day, seasons, or year.

mechanical isolation

species may be anatomically incompatible

Gametic isolation

if gametes of two species meet, cannot fuse to form zygote

postysotic barriers

prevent a fertilized egg from developing into a fertile adult

Morphological species concept

Based on body shape and structure, disadvantage very subjective

Ecological species concept

how individuals interact in their ecological niche, emphasize how individuals adapt to different environmental conditions

Phylogenetic species concept

smallest group of individuals that share a common ancestor

Allopatric

population forms a new species because it is geographically isolated from parent population.

Sympatric

small part of population becomes a new population without being geographically isolated from parent population.

Adaptive radiation

occurs when many new species arise from single common ancestor

Gradualism

Species descended from a common ancestor and gradually divereged more and more in morphology as they aquire unique adaptations.

Punctured equilibrium

Periods od apparent stasis punctuated by sudden change obsrved in the fossil record.

Describe the condition under which new species arise

New species arise when populations become isolated from each other and evolve independently, leading to reproductive isolation.D

How does ecological stability affect speciation rates?

Ecological stability typically leads to slower rates of speciation, while unstable environments may promote rapid speciation due to frequent changes and opportunities for adaptation.

What ecological conditions can lead to rapid evolution?

Rapid evolution can occur in changing or diverse environments, where species must adapt quickly to survive.

What role do environmental pressures play in speciation?

Environmental pressures can drive the divergence of populations, leading to speciation as they adapt to their distinct ecological niches.

explain the processes and mechanisms that drive speciation

Speciation is driven by processes such as geographic isolation, genetic drift, natural selection, and reproductive isolation, which can lead to populations evolving independently and eventually forming new