New Findings Confirm Darwin's Theory: Evolution Not Random
ScienceDaily (Jan. 18, 2008) - According to Darwin's theory of evolution, 
individuals in a species pass successful traits onto their offspring through a 
process called "deterministic inheritance." Over multiple generations, 
advantageous developmental trends - such as the lengthening of the giraffe's 
neck - occur.


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See also: 
Plants & Animals
  a.. Evolutionary Biology
  b.. Mating and Breeding
  c.. Biology
Fossils & Ruins
  a.. Evolution
  b.. Charles Darwin
  c.. Origin of Life
Reference
  a.. Neoteny
  b.. Genetic drift
  c.. Introduction to genetics
  d.. Speciation
An opposing theory says evolution takes place through randomly inherited and 
not necessarily advantageous changes. Using the giraffe example, there would 
not be a common neck-lengthening trend; some would develop long necks, while 
others would develop short ones.

Now, the findings of an international team of biologists demonstrate that 
evolution is not a random process, but rather occurs through the natural 
selection of successful traits. The collaborative study by researchers at the 
Technion-Israel Institute of Technology in Israel, the U.S, France and Germany 
is published in the November 2007 issue of Current Biology (vol. 17, pp. 
1925-1937).

To settle the question about whether evolution is deterministic or random, the 
researchers used various tools - including DNA strand analysis and electronic 
microscopy - to study female sexual organ development in 51 species of 
nematode, a type of worm commonly used to better understand evolutionary 
processes.

When the researchers measured changes in 40 defined characteristics of the 
nematodes' sexual organs (including cell division patterns and the formation of 
specific cells), they found that most were uniform in direction, with the main 
mechanism for the development favoring a natural selection of successful 
traits, the researchers said.

"Since random development would not create such unifying trends, we concluded 
that the observed development was deterministic, not random," said Professor 
Benjamin Podbilewicz from the Technion Faculty of Biology.

The findings, which constitute a significant milestone in establishing and 
reaffirming the mechanism of Darwin's theory, will help in understanding how 
evolution works in all living creatures, said Podbilewicz.

Adapted from materials provided by American Technion Society.

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