Category Archives: biology

A new phylogeny of the mammals

A paper in this week’s Science uses a lot of data to construct the most complete phylogeny yet of mammalian families.  Meredith et al. used 26 genes to not only construct the tree, but estimate divergence times.  Their sample comprises 97%-99% of the roughly 150 described mammalian families. Here’s the tree they get (click to […]

Time to put Andrew Brown to pasture

Many of us who have endured the columns of Andrew Brown at the Guardian feel that it’s time for the man to move on.  His opinions lurch all over the place (usually, however, centered on the evils of atheism and the benefits of religion), but the writing is so absolutely dreadful that it’s hard to […]

Living stromatolite found in Ireland!

Since I’ve posted about stromatolites before, I hope that readers remember what they are.  As a refresher, though, they’re the oldest convincing traces of life on earth: fossilized colonies of cyanobacteria (“blue-green algae”) which date back 3.5 billion years ago—only a billion years after the Earth had formed.  While fossilized stromatolites have been found in […]

One of this year’s Nobel Laureates died Friday

This is really sad: according to Nature and Rockefeller University, one of this year’s Nobel Laureates in Medicine and Physiology, Ralph Steinman, whose prize was announced this morning, actually died of pancreatic cancer on Friday. I’m not aware of anything like this happening before. Steinman was only 68.  It’s not just sad that the man […]

First Nobel of the year goes to three for work on immunology (and a contest)

Damn, didn’t get it again this year!  It’s Nobel season, and half an hour ago the Medicine and Physiology prize was announced: it will be shared by three scientists, the maximum number allowed, for work on both innate and adaptive immunity.  According to the New York Times: Three scientists won the Nobel Prize in medicine […]

Scientists battle malaria using toxic nectar

Yesterday’s New York Times reports a series of studies, funded by the Bill and Melinda Gates Foundation, aimed at eradicating malaria (one report has appeared in Malaria Journal; the reference is given below and you can download the paper by clicking the link at the NYT). The idea is a clever one: female mosquitoes, who are […]

Stephen Jay Gould

Today will be an orgy of remembrance of the events of ten years ago; even at 5 a.m. the television was full of the stuff.  I have nothing to contribute to what’s already been said, so I just want to remember another anniversary that took place yesterday: what would have been the 70th birthday of […]

How many species? I’m still not sure.

by Greg Mayer Jerry recently discussed an article in Plos Biology which tried to estimate the number of species on Earth by extrapolating from more or less known relationships between higher and lower level taxonomic diversity. Carl Zimmer has a piece in today’s Science Times, and records some dissent from the method used: But Terry […]

How many species are there on Earth?

The short answer:  about 9 million, not counting bacteria. That’s according to a new paper in PLoS Biology by Camilo Mora et al. (see also the perspective by Robert May in the same issue; both paper and perspective are free, and you should definitely read Bob’s one-page piece). The issue of how many species inhabit […]

Can species arise in a small space?

One of the big controversies in the study of speciation involves the spatial scale of the process.  Can an ancestral species split into two descendants within a single small area (“sympatric speciation”), or do populations have to be geographically isolated before they can evolve into new species (“allopatric speciation”)?  Clearly the formation of new species […]