Reproduction
The blind cave eel is an animal and
therefore follows the gametic life cycle. This life cycle is the
standard that is taught to nearly every biology student in
nearly every school across the country. The life cycle begins
with a diploid stage. The two diploid parents (a male and a
female) undergo gametic meiosis within special regions of their
body, that is their reproductive organs. The newly formed
gametes are haploid. Then the female deposits the eggs in the
water and the male releases semen. The plasma membranes of the
gametes join, completing plasmogamy. The nuclei join, restoring
the original diploidy to the newly formed zygote and completing
karyogamy.
After these stages, the eel life cycle takes a turn from the traditional animal life cycle. Eels migrate across the Atlantic Ocean to reach their spawning grounds. While this may seem like a fairly normal premise for animals, eels take the process one step further. After their larval stages are complete, most eels exist in a sexually immature form known as a silver eel. This is the stage in which they make their migration. However if they don't make the migration, these eels will never become sexually mature. This is because of a block of the production of a hormone called gonadotrophic hormone. If the eel never makes its migration, the hormone is blocked from production in two ways; through a lack of a hormone that promotes its production and through a dopaminergic inhibition mechanism. Some external factor that the eel encounters on its migration triggers the release of these two blocks and allows it to sexually mature. (Dufour, 1994)
This presents yet another conundrum in the quest to understand the blind cave eel. The blind cave eel is troglobitic, that is it is an obligate cave dweller lacking eye sight and pigmentation. This organism is incapable of making a migration. This presents the question how then do the eels come to sexual maturation and begin to reproduce? Much more work needs to be done on this severely information deficient organism. At this current point in time, any explanation of how the blind cave eels mature and reproduce is merely conjecture.