Kamis, 20 Mei 2010

How do fish do it?


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: fish

Why
: Nicolas Cage only eats animals that have dignified sex.
Nicolas tells The Sun, "I love all animals. I have a fascination with fish, birds, whales - sentient life - insects, reptiles. I actually choose the way I eat according to the way animals have sex.
I think fish are very dignified with sex. So are birds. But pigs, not so much. So I don't eat pig meat or things like that. I eat fish and fowl."
I have never seen fish sex, dignified or otherwise.

Answer
: Some don't! There are 3 ways for fish babies to get made:
  • Oviparity - Lay undeveloped eggs, External fertilization (90% of bony fish), Internal fertilization (some sharks and rays)
  • Ovoviviparity - Internal development - without maternal nourishment - Advanced at birth (most sharks + rays) - Larval birth (some scorpeaniforms, rockfish)
  • Viviparity - Internal development - direct nourishment from mother - Fully advanced at birth (some sharks, surf perches)
While oviparity has benefits (since the eggs are in water, oxygen and nutrients are abundant), the eggs are much less likely to get eaten when carried within the mother. Also, baby fish larva born in the water have to fend for themselves right away, whereas baby fish that come out of their moms' tummies are born fully advanced and ready to eat and fight.

Some fish are even hermaphrodites!

But when they do it, it looks like this:

Source: MarineBiology.com

The More You Know
: Male gobies guard the eggs in a nest until the babies are born. The male yellowhead jawfish actually guards the eggs by holding them in his mouth! WHAT!

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