Chap.24 Speciation Continued Flashcards
Biological species concept is based on
The ability to interbreed and reproduce viable offspring
Four consents of species
Biological
Morphological
Ecological
Phylogenetic
Morphological concept is
Based on body shape and other structural features
Ecological concept of species is
Based on members of a species interact with there environment and the specific niche
The phylogenetic concept of a species is defined as
Smallest group of individuals that share common ancestors on the tree.
Tow types of speciation barriers
Prezygotic
Postzygotic
Prezygotic
Before sperm fertilizes an egg
Postzygotic
After fertilization of the egg
5 types of Prezygotic barriers
Ecological (habitat) Temporal (timing ) Ethological (behavioral) Mechanical Gametic
3 post zygotes barriers
Reduced hybrid viability
Reduced hybrid fertility
Hybrid breakdown
Hybrid breakdown
Consequent generations of individuals are feeble or sterile
reduced hybrid viability
Hybrid development or serial is impaired
- Provides linkage between evolutionary change within individuals
- Is a process
- requires disruption of gene flow
Speciation
RIM’s
Reproductive Isolating Mechanisms
Barrier to gene flow
Accumulation of mutation, genetic drift, natural selection
Genetic divergence and reproductive barriers
Possible secondary contact and hybridization
Class view of speciation