Archive for ‘evolution’

April 28th, 2009

“I just can’t believe in evolution”

Scientific conclusions are not believed in in the same way gods are believed in. blind-belief-virtue

We do not consider scientific conclusions to be absolute truth, we do not worship scientists or credit them with fantastic superpowers. Unfortunately there are no holidays in science. In a totally pragmatic society we’d have to find some other criteria for giving ourselves days-off from work and reasons to get paid for work we aren’t doing. That’s if four and maybe even three day work weeks don’t become more popular first. I don’t doubt economic feasibility studies are already underway.

We “believe” in many of the conclusions science has come to because they make sense in our view of reality and they are conclusions drawn from evidence or consistent with the knowledge we’ve already gained historically. The “belief” of the theist and the “belief” of the non-believer are based on very different degrees of skepticism and the requirements for validity. We do not believe in evolution to the degree a theist believes in their creation story. We do not accept the majority of creation stories because they do not satisfy our skepticism, they do not answer questions to our satisfaction and they offer no evidence of having actually happened.

January 12th, 2009

The world’s only immortal animal

Turritopsis nutricula is a hydrozoan, and it’s considered by scientists to be the only animal that cheated death.

Solitary organisms are (according to current belief) doomed to die, after they completed their life cycle. Hydrozoa are a huge class of predatory animals that live mostly in saltwater, closely related to jellyfish and corals. Eggs and sperm from an adult jellyfish (medusa) and they then develop into polyp stage. Medusae evolve asexually from polyps.

Still, our Turritopsis nutricula managed to find a way to beat that. What these little folks do is they revert completely to a sexually immature, colonial stage after they reach sexual maturity. (Source-ZMEscience)

hydrozoa

I realize the article doesn’t go into enough depth on this, but suppose this behavior can be documented well enough to accept as plausible and possible. How does that impact our old belief that death comes to us all?

Death, the great equalizer. Nothing is certain but death and taxes. Death is the great reward, the deep sleep. For ages it has been the one certainty we could all agree on. We may not have the slightest clue what is going on in life, but we cannot deny that at the end of it all, every single living thing dies. Or does it?

Here’s a case where biology suggests a conflict between reality and the perception that every living thing dies. Maybe we’ve been wrong.

Isn’t it amazing that a simple polyp may possess the ability to do something that humans have wanted to be able to do for our entire history. A simple polyp can do something that religion has promised humanity since antiquity but never been able to bring to pass. All the promises, all the rewards, await us after death. We still all die. I think it’s safe to say that every person alive right now will die. But not this polyp.

On the other side of the aisle, how does this impact scientific presumptions? The presumption of death is pretty widespread. This might add a dimension to “life” that we have dismissed as impossible up to now.

Now that we understand how this process works, will we start to find other living things that practice immortality?

October 5th, 2008

The human barbarian

Two hundred thousand years may seem like a long time to us with our puny 80 year life spans. But on the evolutionary scale it’s not long at all. We are more similar to our early cousins than we are different. There have been modest increases in life span thanks to modern medicine, but physically and mentally we could easily pass for the early humans we’ve evolved from.

Brilliant humans, those who have advanced our species through their discoveries and inventions are unique enough we know about them individually. The vast majority of humanity is still concerned with the same issues our ancestors were; where to find shelter, clothing, food. We still guard our property jealously as I suspect early man did; my cave, my club, my kill. What advancements we have made are due to the insights of a few unique humans and the spread of their insight throughout society. It’s only as a group we’ve advanced at all. Individually we’re not all that advanced.

Humans would still be living in isolated, small groups of hunter/gatherers like our earliest ancestors were it not for socialization. Society, humanity en masse, is responsible for turning barbarians into “civilized” people. Without the social pressure of morals, law and yes, even religion, we would be indistinguishable from the humans who lived thousands of years ago. Morals (ethics), laws and religions were invented by social humans to keep our natures in check, to make it easier for us to live together in increasingly congested cities and towns. Even we atheists have been socialized with concepts borrowed from religions and ethics developed by preceding generations. Humans are pack animals, and every pack has to determine the limits of behavior it will accept and what behaviors will result in expulsion from the pack.

So while I still maintain that as a group humans have advanced in knowledge from our forbearers, individually we are not all that much different than we were hundreds and thousands of years ago. Without socialization we would still be barbarians.

June 7th, 2008

Why our brains are so clumsy

Free thinking, indeed any kind of thinking, is dependent on the abilities of our brains.  Learning more about our brain can give us insight into the process and products of thinking.

In his new book, Kluge: The haphazard construction of the human mind, Gary Marcus aims to take the human species down a peg or two. We might like to think of ourselves as sleek and perfectly-adapted products of evolution, but Marcus instead describes the brain as a clumsy collection of spare parts. If evolution is so powerful, he asks, how did we end up so flawed?

Why do you think that the mind is a kluge?

There are two answers to that. The first is a general argument about evolution: that if you look at evolution it makes a lot of kluges. Evolution tends not to optimise things; it simply tinkers with what’s already there. So it tends to make things better but there’s no guarantee that it will make the best.

The second is an empirical argument. I look to see whether there is anything clumsy about the human mind, and I find lots of examples.

But we tend to think of evolution as something that produces the best possible solution to a problem.

And that’s just not true. Darwin didn’t actually say “survival of the fittest”; I think that was Huxley, but people take that as their crude approximation to evolution. They think that must mean that the fittest thing that could possibly be will survive, but really it means the fittest of the available options. Evolution can’t take a step back and ask what the best option would be; it just works with what it has. And that’s what leads to tinkering and ultimately the kluges.

You’ve said that we tend to think of evolution as a single slope but actually it’s more like a rocky terrain.

Absolutely. You can think of evolution as a process of hill climbing, but it’s a blind process of hill climbing. It can take small steps and it may get higher on the particular mountain peak that it’s on, but it might not realise that there’s a much higher peak off in the distance.

I think that happened with memory. Our memories work reasonably well, but there are much better solutions that evolution just never stumbled upon.

Couldn’t you argue that we are well-adapted for the environment that we evolved in, when we were living in small groups, looking for food? So there’s no problem with our minds, it’s just that the environment has changed.

There are some cases like that. For example, our desire for fats and sugars is mostly tuned to an environment where McDonalds wasn’t around and you couldn’t get these things so easily. But I think that with the memory system, evolution just made a mistake. Probably all creatures would be better served if their memory was better organised, but evolution just happened to go in this one direction. It’s very difficult for evolution to start from scratch and do something completely new.

What’s wrong with thinking of ourselves as perfectly designed, rational beings, when actually we’re not?

Economists make that mistake. They assume that humans are rational, but they aren’t necessarily. And I think that people almost always overestimate their own abilities. They overestimate the quality of their memory, and how careful they are at reasoning. That contributes to political polarisation, for example, where everyone is convinced that they know the truth and nobody else does. I don’t think that’s a very good thing for the species.

What can we do to make our minds work better?

In the long term we may be able to take control of evolution, to adopt new technologies or something like that. In the short term, what they say in Alcoholics Anonymous makes sense – recognition is the first step. We have to see what the limits are and try to work around them.

A good example is that we have this thing called confirmation bias, where we notice evidence that supports our own theories. You can counteract that by forcing yourself to systematically think about alternative hypotheses, and about the perspective that somebody else might take. We don’t do that naturally but we can train ourselves to do it.

Scientists are forced to do that to some extent. But everybody could do with a little bit more humility about their own intellectual powers, and realise that, if somebody disagrees with them, maybe they’re looking at the evidence in a different way; it’s not necessarily that they’re stupid and you’re smart. The more we can recognise that other people are working as best they can from their evidence, that could make us more sympathetic and perhaps we can get along better.

(Source)