The World is Sick

Hatena arenicola

It’s during times like this, when I have to study spherical chickens in vacuums and memorise irrelevant bullshit about consumer behaviour, that my main interest- evolutionary biology- becomes yet more appealing.

Having just spent about an hour reading up on the origin of mitochondria and plastids again, I have stumbled upon something new, as well as some old things that make more sense to me now.

A little background information. The major player in the explanation for the presence of these organelles in our cells is known as the endosymbiotic theory, and I find it positively enthralling. What is basically posits is that at some point, long long ago, a prokaryote- most likely some sort of ancient proteobacterium- was engulfed by a eukaryotic cell, or ancestor of one. In a massive stroke of luck, the prokaryote was not automatically phagocytosed, and eventually became what we know today as mitochondria and chloroplasts.

I was actually reading about the role of apoptosis in unicellular organisms prior to this. I currently have no recollection on how I came to this topic.

Anyway, after a good amount of poking around, I came cross Hatena aernicola. A protozoan flagellate, this little creature possesses an almost science fiction monster/alien quality. It doesn’t look particularly impressive or anything, but its stages of life are most interesting.

Some of the time, Hatena oozes around, eating bacteria and things. This is expected from a protozoan. They’re really predatory animals. Gelatinous lions, if you will. But then, it’s also the Eevee of the jelly world. If Hatena comes across a suitable green alga, it imbibes it into its body and turns into a photosynthetic organism. It stops hunting for bacteria and starts moving towards sunlight.

It’s like eating something, and then getting its powers. Of course, the thing that was eaten is still alive, essentially a slave to a (albeit not that much) higher purpose. The alga doesn’t replicate within the protozoan, so when Hatena divides, one of the daughter cells may be without the photosynthetic ability.

The point is that this is basically a demonstration of an endosymbiotic relationship forming. Assuming we don’t sterilise the earth with nuclear weapons too soon, future generations might be able to watch this amazing relationship make the transition to actual endosymbiosis.

Yes, I have been doing this instead of studying. Aaah.