Wednesday, 4 March 2009

King Sperm and Queen Ova

The last post was written looking at life from the point of view of the most successful of all Bacteria, the strain of Ricketts that produced Ophistokont cells and

The important point being, that we, animals and fungi, are basically vast structures created by a predatory bacterium to enable to better purloin the produce of a hard working strain of bacteria, cyanobacteria.

All 'Life' bigger than Bacteria, is either a parasite or a plant.

And in this post, we treat the parasite as the entity. We're going to look at the evolution of life in a different way again to how we did in yesterday's post.

And- just for once- I'm actually getting a teeny bit of help from Wikipedia. Because for once, even I can't remember the names of all the terms necessary here. The key players in this history of life we don't truly appreciate. The true story of the parasite advance.

I would say that both you and I are parasites. Clearly, we're not plants. But- we're not. Not from the point of view of THIS post. In this post, both you and I are figments of our own imagination. That false belief of ours that we are an individual lifeform is necessary for the master lifeforms that created you and I. Of course, these lifeforms don't themselves have an opinion on the matter. Because they don't think anything at all. But the history of the last nine hundred years of evolution, has been the history of two successful strains of parasites who have managed to do something pretty amazing. And these two strains of parasites have ensured they will spread to the ends of the galaxy, perhaps. In themselves, they are nothing special. But what they have done to ensure their survival and transmission, THAT is pretty special.

The Bikonts, or plants, photosynthetic life, seem on the whole to be quite happy existing on their own, which is surprising. Dawkins points to the huge size of the Redwood trees and notes that with plants, being big is an advantage, because you can capture more photons. And yet only one strain of Bikonts discovered the concept of creating co-operative multicellular organisms. The Green plants, basically relatives of single celled Green Algae. From the Rhodophyta, the Rhizopoda, the Excavata, the Radiolorians and other plantlike Eukaryote, no multicellular forms have arisen. Admittedly, not all of these photosynthesise. They have adopted other niches. But even so, the fact remains that plantlife seems to get on quite well without being big, in spite of Dawkins' point. I guess the answer is, if you live in the sea, it doesn't matter. The ocean is big. There is always access to sunlight. It's only the plants that moved to land found multicellular forms an advantage. The Green plants evolved because only the Green Algae braved the coastal rocks to become moss. On land, industrial production was better served by forming conglomerates.

To be honest, I'm not entirely sure. The evidence suggests that Green plants were first off the mark in forming composite bodies, long before the parasites got the idea. And in a sense, I'm not overly concerned. It IS interesting that plants have developed their own version of sexual reproduction, as in division into two sexes. But that must surely be a parallel development to that seen in the particular set of parasites we are going to look at, for obvious reasons. I mean, I daresay I could read into it and write a similar story for the plants as I'm doing here for the parasites, but since I'm not green and rooted and nor are you, it could be considered to be going off on a tangent. It is worth noting in the sense that it's worth noting the parallels in how multicellular lifeforms have developed, but it's not the story we are interested in today.

Parasites would seem to be greater enamoured of multicellular life. Only that's not quite so. Of the two cell types that all parasites are composed of, the first type, the Unikont doesn't seem to have exactly excelled at it. It has produced slime moulds. Not that slime moulds aren't amazingly co-operative developments. It has been suggested by several that at one time, they were indeed the market leaders in multicellular lifeforms. But, like the Japanese and the technology industry, once the Ophistokonts got going, they outstripped the Unikonts to the degree that now, the vast majority of Ophitokonts are part of a multicellular being.

It would seem that initially, there was no great incentive for a parasite to develop multicellular forms. But once one did, the race was on. And the Ophistokont was better at mastering it.

Why do I say this? Well, because when one comes down and looks at the variety among the Ophistokonts, we realise that there really are only two types of single celled Ophistokonts. And each type of multucellular Ophistokont is related to one of them. In other words, when multicellular life amongst the parasites was first mooted by the slime moulds, each of the existing strains of Ophistokonts produced variants which adapted to it.

The DRIPS are a fairly unimportant group of parasites. Really. We only know of five genera and mostly live on fish. Though clearly their ancestors didn't. There could well be more genera, but they clearly tend to be fairly unobtrusive from our point of view. They are descendants of the DRIPS who didn't become ancestors of the fungi. Or fungal cells, one should say.

The other group in question, is the Choanoflagellates. Cousins of DRIPS and fungi. They have a lot of other, far closer cousins in fact. Many, many different types of Ophistokonts all much closer related to Choanoflagellates than DRIPS or fungi.

And we'll treat all THESE Ophistokonts as the Choanoflagellate family. A family with a fascinating history.

I would say that Choanoflagellates lead an interesting life, but I'd be lieing. They are interesting only in the sense that as far as the rest of the family are concerned, they are kind of like the San are to New Yorkers. They didn't adopt the community life that the rest of the family did. Of course, they enjoy a freedom that their cousins don't. They continue to reproduce themselves by simply dividing. However, one might say they are luckier than the vast majority of their cousins, who exist as slaves, domesticated and bred to serve the needs of the master strains. The master strains, of course, have achieved what the Choanoflagellates never will; literally, world domination, but since they tend to leave their lowly cousins alone, their lowly cousins might well be glad they're not amongst the vast majority of their enslaved eunuch cousins. If they could think of course. Which they can't.

Some of the cousins of the Choanoflagellates still leave a fairly democratic life, as multicellular life goes. Not all have quite gone down the path of tyranny that marks the average parasite colony.
A few hangovers from early parasite co-operative unity still exist.

We call these sponges. And sponges are composed of cells, like all animals. Thing is, when we look closely at them, we can see that all animal cells are- well, Choanoflagellates, pretty much. Or versions of them. Clearly all related to eachother at some point and the Choanoflagellate is their cousin.

The strange thing about sponges, is that in a sense, they are all the same type of cell. Only their not. Actually, the sponge isn't really a multicellular lifeform at all. Not in the way we know it. It's just it refuses to live any other way.

It's actually composed of cells called Amoebacytes, so called because they look like Amoebas. And these creatures will not live apart from their brethren at all. If you separate one from its fellows, it will simply start dividing until a new multicellular sponge exists. But that interestingly is not NORMALLY how the sponge reproduces.

Amoebacytes exist as spares, basically. They are all born as Amoebacytes, but don't all STAY as Amoebacytes. Most don't, in fact. They change into new forms which all have jobs to do in this co-operative. And if we we were to compare them, we'd see that they all appeared to be AS different as different species of Choanoflagellate. Confusing.
If they didn't live together, we'd class them as different life forms. But they all start life as the same lifeform. An Amoebacyte. And they all live together, working together. And most of them- don't reproduce. They have seemingly agreed to hand over the functions of their own reproduction. They will exist in the next sponge, the sponge THIS sponge reproduces, so their descent will be passed on. But not by them.

Most of these cells are unique to sponges. The Choanocytes in fact, the ones on the outside, are pretty much identical to Choanoflagellates. So it can be seen that sponges are kind of a way of preserving the Choanoflagellate 'way of life'. And Amoebacytes are their admin system. Able to turn into the various other types of lifeform needed to maintain the colony. Most of these types don't concern us. But two do. The types entrusted with the task of producing new colonies. Spermacytes and Oocytes.

Spermacytes still look very much like Choanoflagellates, Oocytes less so. It is interesting in fact just how this process happens. Spermacytes say goodbye to their colony and go in search of another. There, they invade the bodies of the Oocytes of that colony, an act suggestive of the original invasion by the Ricketts that drives them into the host of the bacteria that Ricketts made it's home. NOW the Spermacyte drives the Oocyte into dividing. And the Oocyte now produces Amoebacytes, who then decide what cells they need to be. So all the other types get passed on. The Amoebacyte would seem to be the grand master of all these forms, in that it seems to decide how everyone else gets reproduced. But it all muddles along nicely and everyone gets reproduced.

Clearly, all the cells in a sponge are, in a sense related to eachother. They all came from the same Oocyte, fertilised by the same spermacyte. So they all had the same parents.

That is how WE would look at it.

Another way of looking at it, would be that the Choanocytes and the Porocytes and the Myocytes make the ultimate deal with the Amoebacytes. Splitting into two and dividing is a tough job. It uses energy and the new cells will be small and vulnerable. Handing over one's DNA to another lifeform is a risky job, a burden of trust. But if it means you never have to divide yourself, it's worth it. Reproduction is a far more momentous thing for a single celled being than giving birth is to a human. A human being simply opens up and another pops out. A single celled being actually has to divide itself. That's pretty dramatic by comparison. So the Amoebacyte does a deal. It does nothing. It just looks after everyone else' code. The Choancytes GET the food, other cells turn it into energy, other cells feed food to the colony. Every cell now has a simple task. Like a production line. And Spermacytes? They don't do very much at all. Except get fed. One day they'll have to go for a swim. But that's it. Till then, they'll get fed. And then off they'll swim, invade an Oocyte with genetic instructions saying 'Produce Amoebacytes which carry the genetic coding of all the cells that live in our colony'. And the Oocyte then does the burdensomely traumatic task of dividing and dividing again. A lot of dividing. But then again, it's never had to do a second of work in its life up till now.

One is tempted to call Spermacytes 'He'. And Oocytes 'She'. And actually, I don't really see why not. This is where 'He' and 'She' began, kind of. They predate us by a long way. Of course, sponges are neither he or she. But here is where gender begins. Thing is, we would then have to come up with gender names for all the other cells too. In principle again, I don't see why not. After all, this tale centres around 'He' and 'She', but also their allies. In which case, all of us possess all these other genders too. But they don't affect us any differently, because male and female possess all of them in common and they have nothing to do with sex. But Spermacytes and Oocytes, well, most of us have one or the other. And that difference clearly is pretty profound.

Anyway, all this seems to have worked quite well. However, we need to give thanks to one enterprising group of miserly colony dwellers who decided that the colony was kind of inefficient. They could do with a cull of the hangers on.

Trichoplax seems to be the simplest known multicellular lifeform. They aren't abundant and the fact that any still exist at all, is kind of puzzling. What they seem to be- as are 'We'- are descendants of sponge colonies that decided they could do without anyone not strictly involved in the reproduction game. They seem to float around simply absorbing molecules. And that seems to get them by. They consist purely of Amoebacytes, Spermacytes, Oocytes and Myocytes. And here the burdens of this slim down form is that the Amoebacyte gives up it's abilities to administer who becomes what cell- not that is any longer a complex task- and gets into the food absorbing business. Can it still become each of the others at will as it's spongy parallel can? Seemingly not. Or perhaps it still contains the ability in some way that could be switched on, much as an Axolotl can be encouraged by artificial genes to turn into the adult it can never be in nature.

The Trichoplax can perhaps be seen as simplified sponges who decided that maintaining the Choanoflagellate way of life was inefficient and just drifting around aimlessly was somewhat easier. Clearly it was the parasite equivalent of a hand to mouth existence, because obviously the majority of the descendants of the first sponge to try this out began to diversify the cell types again. But one must remember that in a sense, diversifying is the wrong term.

Cells evolve as symbiotic colonies. It is the CELLS that evolve and they evolve to exist in a colonial lifestyle, to fill a niche in the life of the colony. At a larger level, we see this as the colonies evolving, but more accurately, it is the lifestyle of its members.

And of course, lines of descent have become extinct. Not all cell types that evolved survived in all lines.

The question is- are we justified in seeing the eye cells in my body as closer relatives of the eyes in your body than they are to the skin cells in my body?
Because that, essentially, is the thrust of this post. After all, both the eye cells and the skin cell owe their appearance in my body to the same Spermacyte and Oocyte- clearly not the one the eye cells and skin cells in YOUR body owe their origin to.

The point is, we've kind of missed the cleverness of what has happened. Once the gang of four that tried life Tricoplax style had gone their merry way and began to diversify, the colonies of the Choanoflagellate changed. One could argue that in a sense all the new varieties of cells were bred. The colonies became kind of like farms, all the cells aside from Spermacytes and Oocytes became domesticated protists, bred as cows and sheep on a farm for their usefulness to the commune. And they had been neutered. They were eunuchs. Their reproductive powers were held by the Spermacytes and the Oocytes, who do nothing. Nothing except reproduce the whole lot. That is the deal. Most cells in the body do not have to engage overmuch in the arduous process of dividing to reproduce themselves. Just a little phase at the start of the colony at a time when the overall system guarantees them a safe environment. They will live longer and there will be more of them. The stem, of course, means it's all or nothing. Everyone gets reproduced, or no one does. But it's a tame life.

Of course, none of this was thought through. Spermacytes and Oocytes didn't sit around and plan a dastardly plot to enslave other cells and create a Eugenics state. But that is what has happened. Spermacytes and Oocytes have been the ones that were better at the reproduction business and it turns out to be the pivotal talent. So in fact, they haven't had to diversify. Their survival skill has been the codes they carry. That is how Spermacytes and Oocytes live. They pass on code to create colonies of cells to house them. The ones who carry the codes of a range of organisms which work together best, will survive and replicate more.

Why must it be this way? Why has evolution favoured this mode of reproducing multicellular life? An organism that carries code but cannot itself replicate and another which can replicate but only when invaded by the other? Clearly it is favoured by evolution, because species who have reverted to abiogenesis are few and far between and haven't exactly taken the world by storm. But it interesting that the life of all new colonies starts with an act of parasitism. Spermacytes are the ultimate in laziness. But Oocytes haven't survived better by deciding not to wait for invading Spermacytes but instead simply start dividing and reproducing a new colony simply by budding. The Oocytes that have have survived and been passed on in huge numbers are the ones that passively waited for the invasion.

And now let us imagine that Choanoflagellates are actually sentient. A bit silly in some ways, but thought experiments are often a little far fetched, that' the point of them. Who would the Choanoflagellates see as Lord of the Earth?
Well, the Spermacytes and the Oocytes, quite simply. They've ruled the Earth for a good half billion years at least. Since then, the history of life has simply been about then evolving bigger and better colonies. All evolution has been in the other life in the colonies. Evolution has indeed been rapid, but only in the organisms bred by the master strains, better and better fitted to fill specific roles in the collective and useless at anything else. For example, a thrombocyte. These clot blood. They have evolved to do something relevant only within the context of their collective. It has evolved to fill a niche in the body of the colony. It could not exist anywhere else. From its own point of view, its an autonomous organism. It lives a good life.

Osteoblasts. Again, it is hard to imagine what the skills of the Osteoblast would be outside the colony. But it has evolved in a diverse family tree over about four hundred million years to make bone.

We might want to take issue with the point of view the Choanoflagellate would put forward that we aren't real. That actually the unthinking Spermacytes and Oocytes call the shots.

The Choanoflagellate would point out that the Spermacytes and Oocytes have cleverly bred better and better Astrocytes over the years. They send electromagnetic impulses to eachother to set up an information network. And this information network co-ordinates all the information the colony needs. It clearly is an amazing network because it thinks that IT is the entity, but it isn't. In fact it is simply signals being transmitted by the Astrocytes. And the Astrocytes, like everyone else, were bred to serve the Spermacytes in my case, the Oocytes in some of yours.

Well, Choanoflagellate, I have to say I'm actually a little crestfallen. It seems I'm actually not that important. The mind of which I am so proud is actually a network run by the cattle of the Spermacytes!
No wonder this network seems capable of being over-ridden when the Spermacytes start thinking it's time for a swim!
But surely, the Spermacyte isn't that much King! Surely I have more meaning than that.

Choanoflagellate smiles. (OK, silly, but let's pretend.) 'So why then, does the pinnacle of creation so noticeably shout to the world who rules it? Half of you serve the Spermacytes, half of you serve the Oocytes. And which of the two you serve, is the most prominent feature of your design. Or did you forget that? Is not one of the most important points about how you see yourself that you are a 'He'?'

I'm stunned. But of course, the Choanoflagellate is right. If a visitor from somewhere they don't have sexes came down here, they might well assume men and women were different species. They might even think a male gorilla was MORE like a male human than a female human. The Choanoflagellate is right. He and She have even ensured they live in separate homes. They don't just have entire colonies devoted to themselves, evolution has made sure they each of colonies devoted JUST to them.

And that's the proof. Proof that they do nothing. That they truly are the masters. A colony can live and die without them. They really do fulfill no useful function. Men cope without Oocytes, women cope without Spermacytes. No other cells in the body benefit from their presence. But it's too late, they have no choice. They have become eunuchs and they owe their origin to the parents of the Spermacytes or the Oocytes they carry, so they must serve the children all their lives.

The Spermacyte doesn't care that I am typing this. Just as it's forebears didn't. What it cares about is that the system works. That it lives long enough to go for its swim. To pierce the warmth of the Oocyte and hit its jackpot. What 'I' do up till then, doesn't really concern it. In fact, for the Spermacyte, this could kind of be seen as a kind of game the Astrocytes play, keeping trim, keeping the information network primed. But really, the most important thing the Astrocytes are doing right now is remembering there's a cup of tea to my left to pick up.

Well, I'm a little annoyed with the Choanoflagellate for being so smug. So much so I want to point out to him that it isn't real either. It's just imaginary, just as is Mr Spermacyte and Ms Oocyte. All of them are simply devices used by Ricketts to infect the universe.

You see, Choanoflagellate has a very good point. Intelligence is seemingly a by product of the whims of the Spermacytes and the Oocytes. But evolution is random and I would tentatively suggest my Spermacytes have survived by having faith that the system works. Kind of like a Child Emperor who has no idea how his Empire is governed.

I would agree that the entire history of animal life has been entirely the history of Spermacytes and Oocytes and their colonies of slaves.
And I think that we are wrong to see life is simply a family tree and not in fact see it as family trees within tiers.

Prokaryote life is the first tier, with bacterial family trees.
Eukaryote life is the second tier, with two family trees.
Multicellular life is the third tier, with family trees of multicellular forms.

So WE are not related to plants, our family tree, the family tree of 'Animals' doesn't connect to any other. It doesn't connect to Fungi or Plants. These are different formations.

And Animal life is marked by what it is, a series of increasingly complex sets of colonies designed to house the Eukaryote species that rule the Earth; Spermacytes and Oocytes.

The main point I think that I made in the last post was that we should not forget that we are driven by a form of Bacteria that we would otherwise class as a disease. It's a predatory strain of Bacteria. And it behaves like one.

The point to this post is that sex and gender are the underlying feature of existence in a way we don't properly appreciate. Gender division is perhaps the most fundamental division of all. A Man and his dog are both driven by the same Eukaryote, the Spermacyte, whereas women are driven by a different one. Men and women each exist to perpetuate different species, but the passing on of those species is mutually dependent.

I guess this puts a new slant on the battle of the sexes. It is a tension that has always existed. The idea that either could ever dominate seems to be impossible. The Yin and Yang balance is perhaps a far deeper spiritual insight than we realise. Because it sums up the truth of all animal life, the alliance of He and She for their mutual survival.

He and She evolve together, each new strain has two versions, a colony for the He and the colony for the She. Identical in composition for the most part, because the colonies must serve the coming together of He and She. So each animal that exists on Earth today has evolved to propagate the two strains. Crocodiles have evolved to propagate He and She, people have evolved to propagate He and She. Just in Crocodiles it's done by using Crocodile type colonies, in us it's done by producing people type colonies. But perhaps the Spermacytes in us, if they felt anything, would feel kin to the Spermacytes of Crocodiles.

And isn't there a level where we still feel it? That the members of other species that share our gender are ones we kind of understand, perhaps better in some ways than those of the opposite sex of our own species? At some level, perhaps that is true. These strains have kept separate colonies for Spermacytes and Oocytes for hundreds of millions of years. Before intelligence evolved. So the minds of Spermacyte carriers have always differed from those of Oocyte carriers.

And yet remain linked. Mutually dependent.

As if each only sees half the universe.

But this, this is the underlying reality of animal life from the point of view of the Eukaryote life which started it off.
This is how it still is, from their point of view.

It is worth us having contemplated how this third tier of life came about and what the underlying reality is for the tiers beneath it.

And worth us perhaps understanding that it is when a new tier is constructed that real shifts happen in evolution, in the history of life.

And I think we miss the point about what is so amazing about humanity. We are not the first third tier lifeform to reach out tentative steps towards creating fourth tier entities. The insects have experimented with it and made some steps. But reached limits. The termite mound is to the fourth tier, what slime moulds are to the third tier. Not TRUE collective intelligence.
But we might be the first lifeform to achieve it.

And I don't say 'might', I say will.

If we survive.

A million years is not that long in terms of the history of life.

The intelligent star system is coming.


Judith said...

Pretty cool post. It also, oddly, makes me feel as if I need to take a hot shower with anti-bacterial soap and a good loofa.

Anonymous said...

The Yin and Yang of life...are most important to me.

The sperm and the egg...

Light and Dark...

Good and Evil...

Mutual Dependence - definitely.