Mammal Extinction


Something to think about:

A few years ago, a team of researchers in Europe wanted to figure out the answer to a simple question: How long would it take for evolution to replace all the mammal species that have gone extinct in the time humans have walked the earth?

Some 300 mammal species have died off since the last ice age 130,000 years ago. Their answer: It would take 3 to 7 million years for evolution to generate 300 new species. Humans have been around for about 200,000 years. That’s a blink of an eye in terms of the age of the planet. Nevertheless, in that time, we have caused damage that may well last longer than our species itself.

#Evolution #Extinction

Tropical Frogs

As is now fairly well known, tropical frogs are being devastated by the chytrid fungus. The Gamboa Reserve has an enclosed area where many poison dart frogs roam. (They are fed, so are probably no longer poisonous.) They are highly variable in their patterns. Here we have two versions of the green-and-black poison dart frog (Dendrobates auratus).

Also here are two individuals of the strawberry poison-dart frog (Oophaga pumilio). These are examples of the variety called the “blue jeans morph”



It’s DNA Day by proclamation of Congress, celebrating the publication of Watson and Crick’s structure of “the molecule of life’.

On this day in 1953 that Watson and Crick published their groundbreaking paper in Nature suggesting the correct structure of DNA, “Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid“. The paper, the most influential in biology of the 20th century, was only a bit more than a page long. Here is most of the text above:

(Yes, I’m aware of the controversy involving Rosalind Franklin and others).