What are the advantages and disadvantages of external reproduction?

Answer 1

Internal reproduction:

Advantages -

- independent of external water medium (eg. ponds, streams etc.)

- Prevent wastage of gametes and embryo

- Greater chance of fertilisation

- Embryo is nourished and protected

Disadvantages -

- Intermittent organ must be developed

- Complicated behaviour must be evolved to bring the male and femal into intimate contact

Answer 2

Advantages:

1. You don't need to locate a partner and convince them to have sex with you
2. You don't need to wait for your partner to become fertile
3. Every organism in your species can reproduce at one time, thus increasing the chances of the offspring to survive

Disadvantages:

1. Reproduction depends on environmental conditions
2. The offspring are not protected during development, and could easily be killed
3. The chances of your particular sperm and/or eggs being fertilized are smaller than with internal fertilization