Bone Eating Sea Worms: One From the Archives

This is a combination of two posts from the archives…

Continue reading

God Bless America: I am Sick of that Infernal Song

I was idly watching the Mets beat the Dodgers when the seventh inning rolled around and of course they had to sing “God Bless America” so here is one from the archives….

Continue reading

Mammoth Nuclear DNA says African Elephant, Mitochondrial DNA Says Asian: One From the Archives

One from the archives, in which I think out loud and try to solve a conundrum…
Okay, now I’m confused! I have posted on the Mammoth DNA study several times. One of the articles I read stated that Mammoths are more closely related to Asian elephants than African. Yet the story linked to above claims the exact opposite:

A mammoth was chosen for the study, in part, because of its close evolutionary relationship to the African elephant, whose nuclear DNA sequence has been made publicly available by the Broad Institute in Cambridge, Massachusetts (USA). Using comparisons with elephant DNA, the researchers identified 13-million base pairs as being nuclear DNA from the mammoth, which they showed to be 98.5 percent identical to nuclear DNA from an African elephant.

Continue reading

More on Mammoth DNA: One from the Archives

National Geographic News has a story on mammoth DNA:

Continue reading

Mammoth Mitochondrial DNA Partially Decoded: One From the Archives

From December of 2005. The first of three posts on the subject…
According to BBC News the mitochondrial genome of the mammoth has been partially decoded:

It shows that the mammoth was most closely related to the Asian rather than the African elephant.
The three groups split from a common ancestor about six million years ago, with Asian elephants and mammoths diverging about half a million years later.
“We have finally resolved the phylogeny of the mammoth which has been controversial for the last 10 years,” lead author Michael Hofreiter of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, told the BBC News website.


The DNA of several extinct ice age mammals, preserved in permafrost, has been analysed before, but not in such detail.
“It is the longest stretch of DNA [decoded to date] from any Pleistocene species,” said Professor Hofreiter.


The team of researchers – from Germany, the UK, and the US – extracted and analysed mammoth DNA using a new technique that works on even the tiny quantities of fossilised bone – in this case 200 milligrams.
Some 46 chunks of DNA sequence were matched up and arranged in order, giving a complete record of the mammoth’s mitochondrial DNA – the circular scrap of genetic material found outside the cell’s nucleus.

A write up of the research will appear in Nature Online…

How Fossils Are Made: One from the Archives

Via Palaeontologia Electronica

Continue reading

“Junk” DNA and Fruit Flies: One from the Archives

From October, 2005…
Genetics is an interesting, if mind numbingly complicated, subject. As you all know genes are composed of four nucleotides that form pair bonds with each other (to be simplistic). Adenine pairs with thymine and guanine pairs with cytosine. Three base pairs form a codon, etc. Traditionally, a gene is defined as a segment (i.e. series of codons) that code for a polypeptide chain or specifies a functional RNA molecule.

Continue reading