Yannis Stavrou, Diagonios, Thessaolniki, oil on canvas
Calm images of Greek cityscapes. Images of Thessaloniki in sixties - when earth population was around 3 billions...
We have just been informed about questions on Darwin's theory...
Competition isn't the driving force of evolution...
Maybe, the living space is a major factor...
And what about our future? The human population increased dramatically during the recent years: we were around 3 billions during sixties...
Well, maybe the end of humans will come soon. Who is next? The mosquitos, the bacteria - something similar...As for other kind of animals (like mammals etc), there is no future too - due to human actions..
Relative article follows: CalgaryHerald.Com (August 25, 2010)
Questioning Darwin's Theory
A cornerstone of evolutionary theory - Darwin's famously coined "survival of the fittest" - is being questioned by researchers at the University of Bristol, who argue competition isn't the driving force of evolution.
In a paper published Monday in Biology Letters, researchers, including Calgarian and University of Bristol PhD student Sarda Sahney, claim that though competition has been observed on a small scale, there's little evidence it has guided evolutionary leaps in biodiversity.
Rather, animals diversified by expanding into empty living space, first moving further from water, then "continuing to invade new habitats," argued Sahney, co-author of the paper, along with University of Bristol colleagues Michael Benton and Paul Ferry. "Basically what we saw is that the land on earth is so big that these animals have just diversified into the empty space given to them.
"We haven't yet reached a point where, on a large scale, they have to compete with each other."
The research differs from Darwin's popular survival of the fittest theory, which envisioned competition among animals striving for supremacy as the force behind evolution.
According to Sahney, the study suggests that while competition has been observed on a small scale between species, the concept hasn't affected major shifts in biodiversity.
"When Darwin was talking about survival of the fittest, he saw individual animals and species competing with each other for resources," she said.
"On a large scale, we haven't hit that point yet on land."
The study looked at the biodiversity of tetrapods - amphibians, reptiles, mammals and birds - by using fossil records from around the world. It estimated just one third of livable space has been explored on earth so far.
"Animals are still moving into living space. As long as we can preserve the environment that we have, we will continue to see animals diversify because there's just so much space on earth still to be filled," Sahney said.
Royal Tyrrell Museum paleontologist Don Brinkman said the research seems to explore a conceptual shift in the way evolution is studied.
"It's going to stimulate a lot of discussion," Brinkman said.
"Evolution needs the pull of new resources plus the push of competition for animals to exploit those new resources," he added.
University of Calgary biological sciences associate professor Jeremy Fox suggested the study's findings are consistent with Darwin's own theories.
The opportunities to move into new living spaces are fuelled by the competition animals face in their current environment, he argued.
"It's an interesting study, wonderful description of diversification of life. The interpretation is, at least in my mind, completely consistent with and probably reinforces Darwin's insights, which we're still building on today, more than 150 years later," said Fox.
"What the authors have shown is that the diversification of species has gone hand in hand with the diversification of ecological roles those species fill. That's exactly what Darwin himself would have expected."
The study illustrates some of the challenges scientists face trying to explain the fossil record, Fox added.
"The fossil record has given us a record of what happened, not a record of why it happened."
Sahney said the research presents some challenging ideas, adding, "We're not saying Darwin is wrong; we're just saying he didn't have all the information and we can expand upon his theories."
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