Greetings!
So, this week I am stuck with Jury duty and based on the numbers it looks like everyone has left for their various summer fun.
So this week, I offer some cool sea cucumber (cl. holothuroidea) videos!!
Hey Holothurian experts!! Do you know what these are??? Share in the comments!
A "sea apple" feeding
Sea Cucumber Feeding! (from Anilao)
Sea Cucumber Spawning!! (this one from Bonaire)
More Sea Cucumber Spawning! (from Kumejima Island)
A great short clip from "Most Extreme" on Animal Planet
Great blog! I'm a physicist, not a holothurian expert, but I love them (the holothurians), so here are my guesses:
ReplyDelete1. Pseudocolochirus violaceus
2. Neothyonidium magnum
3. Actinopyga agassizii?
4. Holothuria fuscopunctata? Not sure about range.
5. Thelenota anax with interlude by Synapta maculata?
I hope someone who really knows can correct me!
I have a question about the spawning cukes...
ReplyDeleteIn the videos, it appears as if they are just releasing their gametes into the currents at random. Do they just leave their reproductive fate to the tender mercies of ocean currents and chance encounters, or do they at least try to position themselves in places where they sense the presence of others of their species before releasing their gametes into the currents?
Just wondering...Thanks!
Mike,
ReplyDeletethat is a good question! Many if not most marine invertebrates spawn by emitting their gametes into the water and it has been a huge field investigating all of the various dynamics that go into it.
My understanding is that male and female gametes are often drawn to each other chemically. This varies by species but there are often behaviors, such as simultaneous spawning or many individuals of one species clustering all in one spot that optimize the liklihood of a male fertilizing female.
Many are drawn to SOME kind of chemical cue. When one looks at the global but patchy distribution of deep-sea animals, such as some sea cucumbers, one wonders how the gametes of such a species became so widely distributed. Such has been the topic of many a PhD project and NSF grant...
Chris, it looks like the madrepore (ie: gamete hole) is near the head. Is that right?
ReplyDeleteThanks for the vids! I never knew so many others thought cukes were cool. We enjoyed seeing them in the Philippines.