Reverse Evolution

[Dessie32]

Is it possible for a species under certain circumstances to regress? I remember reading about the Almas some years ago. And some of the descriptions seem to tally with Neanderthal Man. But the Neanderthals possessed fire, had toolmaking skills, produced cave paintings and lived in small communities. This seems to differ with reports of the Almas.

The same can be said with the discovery of the Homo Florentis (hobbit) remains. The myths that have come down by local residents about little people surviving in the area where the remains were found. Although the physical descriptions seem to match the hobbits. The survivors seem to be less primitive technology wise. Has anybody got any ideas on this.

Its interesting that it was the opposite when the Mountain Gorrilla was discovered. There had been rumours by local tribes. That gorrilla was a huge manlike beast that wore rudimentary clothes and carried a spear.

 

[Mighty_Emperor]

Regressing is largely a misunderstanding of evolution.

Its all about "fitness" i.e. how well something fits.

It isn't about climbing a ladder or an increase in complexity or even evolution towards some goal.

This is a point Stephen Jay Gould discussed at length a number of times and an especially good piece is his discussion of the evolution of internal parasites. They originate from widely different species with very different body forms but are all relatively simple creatures (the ones in the gut are mouth, gut and reproductive organs - no "but dear reader I married that man" please ) but that is because that is what is required to be optimised for your niche.

On your other points:

1. I doubt if the Alma exists it is a descendant of Neanderthals - possibly some more distant ape but find us one and we'll do the DNA tests

2. We don't really know enough about the Flores finds - the folklore seems to match the finds but more work needs doing. As your gorrila example shows we can't rely 100% on these tales. However, it is possible for technologies to get simpler - at least as represented in the archaeological record so (esp. with such an isolated group) it wouldn't be impossible.

 

[Dessie32]

Thanks for the reply, good points. Some of the eyewitness descriptions of Almas has him with lots of hair. Which was the way science thought the neanderthals would have looked at the time. Where as recently modern thinking seems to suggest that neanderthals may not have been that hairy after all.

 

[rynner2]

Yeah, what Emps said!

Creatures that live in permanent darkness (deep sea, caves, etc) are usually blind, even if they still have eyes. It is not that they are de-evolving, merely that natural selection has no reason anymore to eliminate such blind creatures.

Eventually the eyes themselves will disappear - why waste energy reproducing useless organs?

 

[Pete Younger]

why waste energy reproducing useless organs?


Ahem..no, sorry, this is a serious topic.

 

[minordrag]

Why uselessly waste organ energy reproducing?




what's that--my coat? thanks.

 

[Anome]

One thing that may be considered "regression" is the evolution of birds.

All birds have wings. They are all descended from a flying ancestor, but there are flightless birds - eg the ostrich and the emu. Even more recent developments are some of the flightless parrots of New Zealand.

Of course, none of them have adapted their wings to be forelegs...yet.

Another interesting development is a species of bat that spends a great deal of time on the ground. (Again, I think they are from New Zealand.) They are using their wings as forelegs (an easier development since their wings are closer to the original limbs). While they can still fly, unlike other bats, they prefer to be on the ground for feeding etc.

If I can remember where I can get some references, I'll post them.

As Emperor said, this is not "devolution" or "regression" as such, simply evolution. Given that New Zealand has been isolated for so long, any animals that are there have to either have been there since it became isolated, or had some way of arriving since then. The easiest way to get there is to fly (as with the parrots and bats), but once there the need to fly is removed, and the need to survive pushes towards niches where flying can be detrimental. That and the lack of large predators.

I've explained this less than perfectly, I might re-edit it later to fix it up a bit.

 

[PeniG]

I recently read the article referred to by Emperor (It's in *Leonardo's Mountain of Clams and the Diet of Worms*), and Gould's ultimate point is that these parasites only look simple when viewed simplistically; a parasite which looks at first glance like a sac on a crab's shell not only has a complex "roothead" system and control of the crab's life, but an incredibly complicated childhood and adolescence. The changes undergone by the parasites in question make the caterpillar/cocoon/butterfly sequence look simple.

Futhermore, the "primitive" features of both hobbits and almas are not physical, but cultural, and similar points can be made about cultures as well. It is by no means impossible for an "advanced" culture to transform into a "primitive" one if the primitive one suits changing conditions better. This certainly happened in the Americas, where the great myth of the Moundbuilders arose because the complex, apparently highly hierarchal agricultural societies of the various Moundbuilder tribes had been succeeded by hunter/gatherer/horticulturalists who no longer gathered in large settlements or built impressive landscape features. For various reasons - social and cultural as well as environmental - these cultures became appropriate after the societies that built the mounds ceased to function properly; and they were not only well-adapted to the changed conditions, but as complex as anyone could wish.

It is hard to talk about evolution, cultural or physical, without invoking the shade of the progress paradigm, for the jargon was coined under it. It is even harder not to interpret data egocentricly - yet it is only when we stop comparing ourselves to the observed Other and judging it by ards appropriate to ourselves that we begin to know the Other in its wondrous complexity.

 

[wembley8]

" It is even harder not to interpret data egocentricly "

Quite. Try asking anyone over 50 (or 40? Or 30?) about how art , music or even TV have 'progressed' since their youth. In any century, people will always tell you how degenerate things have become these days.

 

[rjmrjmrjm]

why waste energy reproducing useless organs?

I assume you mean redundant features such as an orangutans cheek 'flanges'. Absolutely huge blubbery growths that can obscure the orangs peripheral vision when he looks down and that have no real purpose. Well its down to sex...

Its the male orangutan telling the females;

'Look at how big and strong I am, I can waste all this energy on making these useless things, I'm soooo good I have spare energy to waste.'

The more dominant the orang the bigger the flanges.

I assume this is true with other animals.

 

[Mighty_Emperor]

why waste energy reproducing useless organs?

I assume you mean redundant features such as an orangutans cheek 'flanges'. Absolutely huge blubbery growths that can obscure the orangs peripheral vision when he looks down and that have no real purpose. Well its down to sex...

No I think he means like our appendix or the whale's rear limbs. As you say those things are under strong sexual selection like peacock's feathers, etc.

 

[Anonymous]

Evolution doesn't have a "direction" as such, although people commonly think it does, especially human evolution, ie the common but false idea that there is some "manifest destiny" to human evolution in the inevitable direction of getting biger and bigger brains and becoming more intelligent, culturally/scientifically accomplished, etc.

IMO that doesn't come from science as such but from (quasi-theistic) Enlightenment socio-historical ideas of "progress" etc, and it implies a "guiding intelligence" behind evolution that there is no evidence for (unless you choose to believe in god(s), 2001-style aliens or some other "intelligent design" theory)...

It's certainly possible for humans to evolve smaller rather than bigger brains or less rather than more linguistic and cultural complexity - plenty of species have started out in one evolutionary path, then "decided" it was wrong and gone back again, such as the flightless birds mentioned above, and probably loads more (eg whales "de-evolving" legs and returning to the sea).

Of course "decide" is the wrong word as species don't "decide" how to evolve... it's random mutations which are then selected for or against by the environment. If the environment changes then a mutuation which was advantageous 2 million years ago can become a disadvantage and if another mutation reverses its effect then the species can go "back" to what it was before... except it's not really "back", it's forward in a different direction, if that makes any sense...

There are plenty of human mutations (syndromes) that lower "intelligence", as we define it, and in our society are clasified as disabilities... but if one of those mutations carried with it some major advantage in a future condition (eg say not having impaired fertility in high temperatures caused by global warming, as present humans might), then people with that syndrome might out-reproduce "normal" people, and human intelligence would decrease... an "advantage" such as higher intelligence may not actually be an advantage if it's genetically linked to a disadvantage, eg. lower fertility...

 

[Pete Younger]

why waste energy reproducing useless organs?

Actually, I was quoting Rynner.

 

[rynner2]

Actually, I was quoting Rynner.

Don't life get complicated!

(On another thread, I've been 'accused' of using a triad, no less!)

 

[Anome]

Goldstein makes some valid points. There is a danger in discussing evolution of assuming that it has a life, or intelligence, of it's own, and that there is some over-reaching plan involved.

This is the essence of the Intelligent Design argument, which, let's face it, is just a load of crap cooked up by Creationists to discredit Evolution.

 

[rjmrjmrjm]

Excuse me for being slow, very very slow, and possibly off topic... but I just realised that Creationism and Evolution do not have to be exclusive of each other.

Coo...

 

[jarmaniac]

This is the essence of the Intelligent Design argument, which, let's face it, is just a load of crap cooked up by Creationists to discredit Evolution.

I think you'll find Intelligent Design was going well before Evolution was mooted (e.g. Paley, who came up with the watch/watchmaker analogy which Dawkins picked up on much later).