From the Stage 2 SACE Biology course outline, this video discusses:
- Different criteria are used to define a species depending on the mode of reproduction.
- A species that reproduces sexually can be defined by the ability of its members to actually or potentially interbreed to produce fertile offspring.
- Other criteria used to define a species include:
– morphological similarity
– biochemical similarity
– sharing a common gene pool.
- Reproductive isolating mechanisms act to maintain distinct species.
• Describe pre-zygotic (prevention of zygote formation) mechanisms including:
– temporal isolation
– behavioural isolation
– mechanical isolation
– gamete isolation.
• Describe post-zygotic (prevention of fertile hybrids) mechanisms including:
– hybrid unviability
– hybrid sterility.
