Scientists discover first multicellular life that doesn't need oxygen | Hacker News Reader

Scientists discover first multicellular life that doesn't need oxygen

physorg.com

60 pointsdantheman17 comments

Totally cool. The headline can act as the tl;dr summary, but basically they found 3 different species in the same family in this weird corner of the Mediterranean. They don't need any oxygen because they have something other than mitochondria in their cells to produce energy.

Given their unusual properties I wonder how likely they are to be seeded from 'alien' matter rather than derivatives of known Earth lifeforms.

Very unlikely indeed. They are new species but have been classified into previously-known taxonomic groups. They're related to other, perfectly prosaic Earthly animals.

Thanks

Please don't down mod comments when they aren't trolling.

The parent comment is at -2 points at the time of writing, which is very unfair. Just argue the comment and leave it at that.

Appreciated

given the similarities in the environments we and they evolved in, (ie Earth) I think it's likely that you have wildly more in common with these lifeforms than with any you'd find elsewhere.

The organelles they use for anaerobic respiration are found in other unicellular eukaryotes (single-celled organisms that aren't bacteria, like some fungal pathogens). The interesting thing here is that they're multicellular, not that their cellular biochemistry is unique.

Thanks, my biology is weak so there's a couple of key terms for me to check up here!

So what is it that they have in place of mitochondiria?

A fascinating book "Power, Sex, Suicide: Mitochondria and the Meaning of Life" (http://www.amazon.com/Power-Sex-Suicide-Mitochondria-Meaning...) suggested that the multicellullar organisms on Earth evolved only once, when the symbiotic relationship between two types of bacteria was formed - one of them became "host", and the other became mitochondria and specialized for energy production.

The book suggests that the conditions for this to happen were very unusual and are unlikely to ever happen again. It does even suggest that this may mean that life in the Universe, more complicated that single-cell organisms, is very unlikely to evolve.

If eukaryotes evolved more than once, then there's some more hope for extraterrestrial life I suppose ...

> If eukaryotes evolved more than once, then there's some more hope for extraterrestrial life I suppose ...

Wouldn't you call extraterrestrial bacteria `life'?

Well, most people think multicellular when they get excited about life because multicellular is how earth life gets complex. To that end eliminating flukes that happen only once is important.

OK. I am not that discriminating. (Actually, Archae and Bacteria are much more interesting too me.)

They use hydrogenosomes, or something similar, instead:

http://en.wikipedia.org/wiki/Hydrogenosome

It looks like the metabolic reaction is somewhat similar to the aerobic one used by mitochondria, but uses hydrogen ions instead of oxygen molecules. Hydrogenosomes may or may not be evolutionarily related to mitochondria.

Here's the original journal article (open access):

http://www.biomedcentral.com/1741-7007/8/30/abstract

This is exactly the sort of example needed for evolutionists to point to to say "see, it can happen in terrestrial time periods". A puny 50k years, and we appear to have multicellular creatures which evolved to not need oxygen. That's way more than mere adapting, that's a fundamental, radical change.

You may be able to impress the undecided by-standers (and that's important). Don't count on winning over anyone who's decided that evolution doesn't fit into their world, at least not with rational arguments.

P.S. This is meant as a comment on the limited reach of arguments in convincing. I don't want to start a discussion on creationism.

Mars next?

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