Speciation Flashcards
Species
Populations of individuals that can interbreed under natural conditions and produce fertile offspring
Speciation
The formation of a new species from existing species
Macroevolution
Forming of a new species
Reproductive isolation mechanisms
Any heritable feature of body, form, functioning, or behaviour that prevents breeding between one or more genetically divergent populations
Behavioural isolation
Prevents other species from recognizing or selecting them for mating
Temporal isolation
Two species that live in that same habitat or the same niche but have different mating seasons due to varying reproductive cycles
Ecological isolation
Two species that live in the same general area but in different habitats
Mechanical isolation
Structural differences in reproductive organs that prevent fertilization
Gametic isolation
If egg and sperm from 2 different species do happen to meet gametic isolation will ensure that zygote doesn’t form
Hybrid breakdown
Hybrid forms but when these hybrids mate their offspring are weak and sterile
Hybrid inviability
Development of hybrid zygote stops in early development and it dies before birth
Hybrid sterility
Cannot produce normal gametes
Types of speciation
allopatric, adaptive radiation, and sympatric speciation
Allopatric speciation
Occurs when populations are separated by geographical barrier and diverge genetically
Adaptive radiation
The change of a common ancestral species into a variety of differently adapted species
