Advantages and disadvantages of internal & external
Internal-dis
Higher risk of sexually transmitted diseases being passed on
Internal-ad
Inscrease chance of gametes meet
External-dis
Large amounts of gametes go unfertilised and wasted
Internal-ad
Less chance of diseccation of gametes
Internal-dis
Limited amount of offspring being produced at any given time
External-ad
More genetic variation
External-ad
Easier to find mates as the gametes released can drift (wind,water etc)
External-dis
Environmental hazards such as predators reduce the change if surviving into adulthood
External-dis
Greater chance of desiccation of gametes/zygotes
Internal-ad
Greater change of successful fertilisation
Internal-dis
Harder to bring both male and female into intimate contact
Internal-ad
More protection against outside environments and predators, and therefore a higher chance of surviving until birth
Internal-ad
More selective of their mates
External-dis
Not guaranteed that sperm will come in contact with eggs
External-ad
Results in the production of a large number if offspring