Reproductive strategies
- Created by: katie
- Created on: 23-03-13 15:56
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- Reproductive strategies
- Gametes are shed in water and fertilisation is external
- Heavy waste of gametes which fail to fuse
- Embryo is entirely dependent on yolk supply for its development
- Many hazards – predation etc, - large waste of embryos
- Finding suitable conditions for development is a completely random process
- Terrestrial mammals have internal fertilisation
- Placing of gametes/female gametes not shed
- Greater certainty of fertilisation.
- Number of eggs has been much reduced
- Internally developing embryo not dependent solely on yolk / importance of placenta
- High level of protection from external hazards during development
- In general more time / energy / resources devoted to fewer offspring
- Contact between parent and offspring; parental care
- provision of dens/ burrows/ herding/ protection from predation etc
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