Coelacanth biologygreenspun.com : LUSENET : South African Coelacanth Conservation and Genome Resource Programme : One Thread
Hello, I've done a bit of reading about coelacanths but much has been learned recently. Have any pups been sighted from Jago? Do we have any estimates of gestation time? Is it known whether the mother fish watches over the pups at all, as some fish do?
Is it true that the coelacanth egg is the largest known egg of any animal? (This could not be true if one is including ostrich eggs but since the bird's egg is partly yolk and albumin covering, perhaps in a strict sense it is true?)
Was there any conclusion made about whether the "headstanding" position of coelacanths observed in the Comoros was a natural behavior, or caused in some way by the submersible?
Thank you, Joanie Livermore, Oregon, USA
-- Joanie Livermore (email@example.com), May 31, 2002
No pups have been sighted from Jago anywhere.
Gestation period is estimated to be about 13 months.
We know nothing about the life of juvenile coelacanths. Whilst it is possible that the mother might take care of the juveniles, it is more likely the mother gives birth and then leaves the young to fend for themselves, like sharks do.
The coelacanth egg is the largest known fish egg - it's about 325g in weight and roughly the size of a grapefruit - HUGE! Ostrich eggs as you point out are bigger and heavier. I have not seen the yolk of an ostrich egg, so I'm not sure. Coelacanth eggs are basically all yolk.
No firm conclusions have been formed about the headstanding behaviours; theories include disturbance by the lights of the sub or electrical fields emanating from the sub. However, the headstand might be a natural phenomenon that coelacanths do for instance when hunting prey - coelacanths are thought to have an electrosensory organ (rostral organ) in their snout which would be useful for hunting in the dark; maybe they adopt this position whilst hunting.
We still have a lot to learn!
-- James Stapley (firstname.lastname@example.org), July 11, 2002.