Metal Slug

This is an entry about invertebrates. You have been warned.

What do you first think of when you see the word, 'Gastropods'? A stomach? A garden snail? Or a platter of half a dozen of baked escargots dripping with garlic butter? For me, it was usually snails, until I met one member of the subclass called the Opisthobranchs: the faithful nudibranch.

Yes, it is all jargon to you, but the nudibranchs - as we all so lovingly call them- are also known as the sea slugs. They are also known as the gems of the oceans. And from the beautiful pictures that many have taken of these beautiful creatures, I present to you my personal favourite - Glaucus atlanticus - the Blue Sea Slug.

Glaucus atlanticus, the blue sea slug. Pictures taken from http://www.nudibranch.com.au.

It looks like something that is derived from science fictions or pluck out of fantasy stories, but indeed, fact is often stranger that fiction. These nudibranchs hang out in clumps of seaweeds known as Sargasssum, and unlike most other nudibranchs, the members of the genus Glaucus do not need to stick to a substrate to move. As you can see, they float above the substrate and basically just let the currents take them wherever it fancies. At the beginning of this year during my Marine Bio camp, I came across a book on nudibranchs and while browsing through the myriad of sea slugs, I came across a beautiful picture of this little dude.

If I would have a tattoo, I would stylise a picture of this dude and use it. Yes I know, I am a complete nerd. Point and laugh at me now.

Glaucus atlanticus (left) and Glaucus marginatus. The latter is a smaller species but no less ornate and beautiful. Pictures from http://www.nudibranch.com.au

Also as a justification of me setting up a blog (if there was ever such a thing or a need to do so), I set up this blog with the idea of recording my research progress next year. Although whether or not I might get into honours is still hanging in the air, but I am going to fight tooth and nail to get into the program. Firstly, because it is a step I need to reach my goals as an academic. Secondly, how can one resist not to work with leeches??? Well, even though that is still unconfirmed as well, but well, I have done the best I can and now the powers of decision is out of my hands.

So this is a little teaser on the little things I hope I will be working on next year, the snail-eating leech, Helobdella papillornata (Euhirudinea: Glossiphoniidae). The Glossiphonids are renowned for their parental care - yes, leeches have parental care too. Chew on that. I will write more about this dudes once I get my confirmation. Fingers crossed.

A brooding leech. These leeches laid typically 20 - 60 eggs which they tend and when the young hatch, they stick to the parent leech for up to 4 weeks. The young leeches will then feed on snails captured and digested by the parent during that time. The parent on the other hand, does not feed during that brooding period (Govedich and Davies, 1998). Photo from http://www.invertebrate.us

Reference (I heard groans and moans)

Govedrich F.R., Davies R.W., 1998, 'The first record of the genus Helobdella (Hiruninoidea: Glossiphoniidae) from Australia, with a description of a new species, Helobdella papillornata,' Hydrobiologia, 389, 45-49

For your entertainment reward, just scroll down and enjoy songs from Bonnie Pink and Hajime Chitose. :p Ta.

She A Male, He's A Male

I was browsing through youtube.com last night - with my trusty cooper in tow- when I chanced upon this silliness of a commercial. (Unfortunately, the uploader of that video did not allow embedding of it so you need to click the link to watch it. By the way, the female narrator said "Strong and beautiful"). Not that it is not effective but trust the Japanese to really sell their products. Anyway, my friend commented on the violent woman and that got me thinking about hyenas. So yup, here you go, a little write-up on the quirkiness that is the hyena. ;)

The Spotted Hyena (Crocuta crocuta)

Photo by Steven Glickman, in Alcock 2001 'Animal Behaviour'

For your info, that's a female in the picture. Like several other animals, the spotted hyena females have a pseudo-penis which they happily flaunt to everyone in the vicinity. For a better idea of how they do so, go look at dogs next time they greet each other, especially the males. This so-called inspection of the genitals is a form of dominance assertion. Dogs, feral and domestic, often sniff the female's butt, not because they like the smell - there is a possibility but I will give you the liberty to exercise your imagination here - but to 'check' or inspect the genitals of the female so as to assess if she is a good mate for him. Similarly, such a system exists in hyena and it seems that the females have adopted a inspection of the pseudo-penis as a form of ritualised greeting.

At this juncture however, I would like to point out that the pseudo-penis is just that: it is fake. It serves no purpose at all to the female hyena, quite unlike the panda's thumb. On the contrary, the development of a pseudo-penis however can be fatal to the female when she gives birth. Most of you know how the womb and contractions function, so I will skip that. In the female hyena, the birth canal does not exit the normal path - through the rear of the body, near the anus. Rather, the birth canal runs through that pseudo-penis. Now let your imagination run again. Yes. It is often fatal.

Yet, evolution has favoured for the development of a pseudo-penis, despite the obvious disadvantage to her. If you frequent Animal Planet or NGC or Discovery Channel, you would have seen packs of hyenas in all their vicious glory, fighting and squabbling, growling and biting their way into meals captured by other predators on the savanna. The savannas are a harsh place to eke a living. Any advantage that the hyena might gain will put them ahead of the race to survive there.

The female spotted hyenas are loaded with a potent androgen cocktail (male hormones similiar to testosterones). This hormonal infusion boosts the level of aggressiveness in the female, as well as making her the toughest, the strongest and the most short-tempered of the lot. Come dinner time, she will be able to body her way into the centre of the feeding frenzy and gorge herself silly on the carcass. However, the hormonal boost endows her with masculine characteristics, maybe even more so than the males. She is bigger than most males, ranking higher in hyena hierarchy then them, and as we see in the picture, she develops a pseudo-penis. Therefore, despite the possibility that she might die giving birth, the androgens puts her at the top of the hierarchy. And in the wild, we all know that those are the survivors.

There are more quirky gender issues in the animal world, but I think I'll leave it as that now. Now for something else that I plucked from youtube.com. I just can't have enough of Japanese commercials. :grin:

::Reading:: Jonathan Strange and Mr. Norrell by Susanna Clarke
::Listening:: Depapepe - ハチロク~