species

Species

a group of potentially interbreeding individuals that are reproductively isolated from other such groups ( other species )

Population

A group of actually interbreeding industry that are reproductively isolated from other such groups ( usually more than one population in a single species)

Biological Species Concept

species as group of organisms that can interbreed in nature to produce viable, fertile offspring, emphasizing reproductive isolation from other groups

Morphological species

defines species based on shared physical characteristics like size,colour, and shape. Essentially grouping organisms that look a like into the same species

Ecological species

organisms adapted to a specific environment niche, using resources and interacting with their habitat in similar ways

Phylogenetic species

defines a species as a group distinguished by unique genetic or morphological traits

Focused on ancestry and descent rather than interbreeding ability

Population ( based on biological species concept )

group of interbreeding individuals of a species that live together in a specific place

Subspecies

group of organisms that can potentially interbreed but have different selective pressures from other such groups. like living different environments/ regions

May be the intial stage of separation between populations of a species

Reproductive isolation

Maintaining species differences

Hybrid

Offspring of mating between different species

Speciation

The formation of new nd distinct species in the course of evolution

Cladogenesis

branching evolution where one lineage splits into multiple new species

Anagenesis

gradual directional change within a single lineage

Pre zygotic mechanisms : ecological

Species live in different habitats/niches

Pre zygotic mechanisms :Temporal*

Species breed at different times

Pre zygotic mechanisms : behavioural

Species cannot communicate/recognize

Pre zygotic mechanisms : Mechanical

Species cannot physically mate

Pre zygotic mechanisms : Gametic

Species have non matching receptors on gametes (incompatibility)

Post zygotic mechanisms: zygote breakdown

2nd generation hybrid offspring have reduced survival or fertility

Post zygotic mechanisms: hybrid sterility

Hybrid offspring cannot produce gametes

Post zygotic mechanisms: Zygote death

Zygote doesn’t survive therefore cannot reproduce

Post zygotic mechanisms: hybrid inviability

Hybrid offspring do not complete development