Fingers

Fingers

A hundred years ago, scientists really tried to understand why we have five fingers, why giraffes have a long neck.

It was a Franco-British fight, the winner being Darwin.

Explained for a school class, Lamarck explained that as the vegetation changed, as the trees where getting taller and taller, the antelopes would adapt and their neck would become longer and longer. If you think this is nonsense, look at yourself when you are driving on a motorway and then changing over to a country road, you are adapting the speed at which you are driving. There was nothing impossible in assuming that our genome was so clever that it could respond to environmental changes.

Darwin, explained at the level of a school class, believed that animals that could not reach the food as it was too high, would die and only would survive those with longer and longer necks. It is the accepted theory but of course pure nonsense unless you can support it by a proper probability analysis, but where would you get the figures?

Stephen Jay Gould wrote much better on this subject. In a nutshell, Stephen Jay Gould is asking whether Evolution has a vector. We have all been brought up with the images of Evolution going from simplistic life forms and ending with us, the Ultimate Expression for Perfection, it being understood that after having reached the stage of "Man", Evolution can vanish and have a rest, as it has reached perfection. Man will now take the Responsibility for his own Evolution by controlling the DNA and Genetics.

Incidentally, when I was a child, we would be told that millions of years ago,a living animal, that had always lived in the ocean, would creep into marshes, then as the marshes were drying out, would develop a capacity to life ouside of the water. It is of course pure nonsense unless you can run a statistical probability support.

Here is the reverse situation

A living form migrating from land to the ocean

http://news.bbc.co.uk/1/hi/sci/tech/1974869.stm

Wednesday, 8 May, 2002, 18:29 GMT 19:29 UK

How whales learned to swim

The earliest whales were wolf-sized land mammals

The mighty blue whale owes its swimming ability to an anatomical quirk.

Fossils show early whales became agile swimmers in a mere blink of evolution - about 10 million years.

Scientists believe the ancestors of whales were land animals that crawled into the sea to escape predators or seek food.

The mammals gradually lost their limbs and became fully adapted to living in the ocean.

According to new evidence, published in the journal Nature, one of the secrets to adapting to a marine environment was a scaled-down inner ear.

This semi-circular canal system gives land mammals, including humans, a sense of balance.

We only become aware of its role when something goes awry - such as feeling drunk, sea sick or riding a rollercoaster.

Animal acrobats

Modern whales, dolphins and porpoises (cetaceans) have similar inner ears to land mammals.

These are smaller, size-for-size, than land-dwellers. Our inner ears, for example, are bigger than those of the blue whale.

However, unlike say a large elephant, a whale can make acrobatic leaps and turns without experiencing vertigo.

This is thought to be because its smaller inner ear is less sensitive.

Fossils show that the inner ear of early whales evolved rapidly after they entered the sea. The adaptation enabled early whales to swim without becoming dizzy.

Marine diversity

Primitive whales probably became fully aquatic about 5-10 million years after they took to the sea about 50 million years ago.

It may sound like a long time but it is remarkably quick in evolutionary terms.

Rich Lane, director of the US National Science Foundation's palaeontology programme, which funded the research, said: "The early evolutionary development of small semicircular canals by cetaceans opened an entirely new mammalian niche for habitation and contributed to the broad diversity of marine living habits that we see in whales today."

He said the evolutionary acquisition of such specialised organs or abilities - like the brain and upright walking habit of man - provided mechanisms by which highly evolved organisms dominated in certain environments.

In short, it explains how whales came to rule the oceans.

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