Mean colour of visible spectrum?

[sophiecentaur]

Here's an study which finds that "Caucasian Boys Show Highest Prevalence of Color Blindness Among Preschoolers" http://www.aao.org/newsroom/release/color-blindness-among-preschoolers-ophthalmology-journal-study.cfm

"Researchers from the Multi-Ethnic Pediatric Eye Disease Study Group tested 4,005 California preschool children age 3 to 6 in Los Angeles and Riverside counties for color blindness. They found the following prevalence by ethnicity for boys:

• 5.6 percent of Caucasian boys
• 3.1 percent of Asian boys
• 2.6 percent for Hispanic boys
• 1.4 percent of African-American boys"

Interesting figures. From a very simplified viewpoint, it might imply that it relates to the amount of Sunlight experienced in the different regions.

 

[fizixfan]

Interesting figures. From a very simplified viewpoint, it might imply that it relates to the amount of Sunlight experienced in the different regions.

That makes a lot of sense. An exception is Eskimos (Inuit), who are only about 1% color blind, but "it is logical to assume that less of the ‘original Eskimos’ carried the defective gene, so the likelihood of it infecting the gene pool was quite a lot lower." http://www.colour-blindness.com/general/prevalence/

 

[sophiecentaur]

That makes a lot of sense. An exception is Eskimos (Inuit), who are only about 1% color blind, but "it is logical to assume that less of the ‘original Eskimos’ carried the defective gene, so the likelihood of it infecting the gene pool was quite a lot lower." http://www.colour-blindness.com/general/prevalence/

Of course, when you say "defective", it may be more to do with the actual need for that particular characteristic and a consequential (Lamarckian style of )adaptation. Lamarck is not as far out of favour these days as he was.

 

[fizixfan]

Of course, when you say "defective", it may be more to do with the actual need for that particular characteristic and a consequential (Lamarckian style of )adaptation. Lamarck is not as far out of favour these days as he was.

I agree absolutely. I was just quoting the source. "Abnormal" may be more to the point. Epigenetics seems to be lending more credibility to the inheritance of acquired traits. I've always thought that the Darwinian view of evolution as nothing more than random mutation and natural selection was incomplete. It completely ignores self-organization and emergent order.

 

[sophiecentaur]

Read Arrival of the Fittest by Andreas Wagner. It's a good read and shows, with computational evidence, that there are many pathways to the same end result so that the actual statistical probability of evolution in a particular direction can be much higher than intuition (on a simple Darwinian basis) would suggest. It 'explains' convergent and parallel evolution. Great stuff but not Physics.

 

[fizixfan]

Read Arrival of the Fittest by Andreas Wagner. It's a good read and shows, with computational evidence, that there are many pathways to the same end result so that the actual statistical probability of evolution in a particular direction can be much higher than intuition (on a simple Darwinian basis) would suggest. It 'explains' convergent and parallel evolution. Great stuff but not Physics.

Sounds interesting. I read the intro, and it's a tease. I probably will buy the book to see if he really does explain HOW nature innovates.

Stephen Jay Gould's "Punctuated Equilibrium" introduced the idea that genetic changes accumulate over time with no changes in phenotype, and will sometimes be expressed suddenly (relatively speaking) when the right amount of environmental pressure is brought to bear.

I would also recommend Stuart Kauffman's "At Home in the Universe," a groundbreaking book that looked into the roles that self-organization and emergent order play in evolution. Kauffman was a MacArthur Fellow, so he's no slouch. This book was quite revelatory to me.

 

[sophiecentaur]

if he really does explain HOW nature innovates

What he does do is to show the results of a vast amount of statistical work on computers which has revealed that there are many different pathways to achieve a seemingly 'singular' result. The numbers / probabilities leads to the conclusion that evolution does;t have to rely on such low probabilities which would be associated with single random events. I guess, when you get down to it, it's akin to comparing _nC_m and _nP_m (Combinations and Permutations). He writes numbers down with a lot of zeros in them, when he wants to make a point - to appeal to the non-mathematical amongst his readership- but it's quite a good read and I came away 'feeling' I had a better grasp of the situation. Kindle prices are always better than hardback, of course. Fine for a book with very few diagrams in it.