The Gaming Den

Volunteer services won't care about your health, while the military requires exemplary health of all its members.

So yeah, as long as you can take care of your own needs, being able to do things like count boxes, hand out boxes - well, that's often what volunteers are doing.

-Crissa

I'm back. I'll talk about it tomorrow.

-Username17

sigma999 wrote:

Frank wrote: ... because as a biologist I can expound at great length about the common descent of animals and the effectiveness of adaptations which causes convergent evolution of relatively unrelated animals living in similar situations ...

O RLY?
Tell more! I'm a biologist-wannabe.
What's so different about the animals you saw?

Evolution is a funny thing. All the simplified descriptions of it that you get are probably simplified enough to be flat wrong, but I'll do my best to get it out there. Very basically, "Selection" is a horrible process whereby every single copy of something dies before it has a chance to reproduce (and yes, this can take many generations of slow dwindling or happen all at once in a fiery explosion). There is literally no such thing as a trait which is "selected for" things are only selected against.

Now, selective pressure comes in many forms. Some of it is literally random - if your set of genes happens to be sitting at ground zero for an asteroid strike, every copy of that set is wiped out. Some of it actively goes after having or not having specific traits. There are competitive pressures, whereby there is a limited amount of available resources and being better at collecting them acts as a selective pressure against other creatures who are not as good. There are also non-competitive pressures - when a new toxin or deadly virus is introduced to the environment, then every creature that is killed by such will die and the relative strength of other creatures is essentially irrelevant.

The paradigm of evolution is that there are mutations and there are selections. Traits, both physical and chemical which are helpful to survival have no special reason to appear in the first place, but once they occur they are relatively unlikely to change over time because those children born with mutations of those helpful traits will usually die. Physical traits are especially interesting because there is no "thumb gene" that makes thumbs happen, there are simply a number of developmental regulatory genes (and even non-coding structures in the DNA folding) which create a fractal pattern that grows itself into a shape that may or may not have thumbs. The human thumb and the panda thumb are not even composed of the same bones, it's an entirely different growth pattern that happens to fulfill a similar function - and in either case a panda or human born without thumbs is unlikely to survive and have children so those structures are kind of locked in for each species.

The most powerful and useful protein in the entire world is cellulase. It is an enzyme that converts cellulose (the primary structural component of plants) into glucose (the primary food source of all life). Any animal that had it would be able to eat saw dust and grass and get functionally the same caloric intake from it as eating granulated sugar. But no animal has ever evolved it. There is literally not one single animal on the planet that has ever randomly assembled that protein. If one developed it, one would imagine that it would probably stay one generation to the next, but none of us ever had.

-Username17

Call me stupid, but I've been convinced by the acts of evolution itself that Lamarckism is, on some level, actually valid.
However, it occurs on such a small scale as to be nearly invisible.
Not in a sense that cutting the tail off a dog creates a breed of tail-less dogs, but in that there are far too many times when it's almost as if evolution occurs conveniently when odds are stacked against an ecosystem, genus, population, or whatever.
Like, pre-emptive evolution in preparation for disaster.

What's the word.. intelligent design.
Although, more like mutations directed by a collective subconscious.

It would make an interesting thesis, and I don't put any emotional investment in the subject, but if anyone proved such a thing correct I dread its unanimous rejection by both religious and scientific communities.

sigma wrote:Like, pre-emptive evolution in preparation for disaster.

We call this "bio-diversity." See within a healthy population there is a lot of genetic variation, a lot of mutations have effects that are currently only mildly beneficial or harmful (or even just straight irrelevant), and those just sit around getting passed from some of the population of this generation to some of the population of the next generation. Generation after generation until something happens that makes those mutations important. And when the heavy axe of selection comes down and takes away all the creatures that have a specific trait that mutation vanishes from the host population and a generation later it's like it never existed. And when selection comes for everything that doesn't have that trait, the entire remaining population will have that mutation and it won't be considered a mutation anymore because literally every single member of the species will in future generations be descendants of the sub-population that had it.

For example: we have a very small number of humans who have a genetic anomaly that gives them an extra finger. If some event kills off all the humans with six fingers, we'll lose that trait altogether. But if an even more horrifying event comes along and kills off everyone without a sixth finger then having a sixth finger will become the norm. The total human population on Earth would of course be very small at that point, but within another hundred thousand years the whole Earth could easily be repopulated - and that's basically an eyeblink in geologic time.

So when we look back through time in the dirt we see many events where a species was killed off down to just a relative handful of examples on one extreme or another of its potential variation - and when its numbers recovered the species looked totally different because the old extreme was now the center of the new bell curve. And geologically this looks like a very sudden shift in a species' morphology - but in the experience of the animals living it the series of events was generations long and involved a nearly complete die off followed by a recolonization by the children and the children's children of the scant survivors.

But no, there is no Lamarckianism going on. If a species doesn't happen to already have the needed traits somewhere in its variation when the selection events happen, the whole species simply dies out and then there is no "next generation" at all. This happens all the time. Looking back it is tempting to say that the current reality was somehow inevitable, that there was some sort of purpose to everything. But there wasn't. While we happened to roll a 13, we could have just as easily rolled a 2; and we were going to roll something.

-Username17