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Highly Evolved

If the title of this post makes you cringe, then you belong to a minority of people who realize why the phrase “highly evolved” is so wrong. Unfortunately, “highly evolved” (as an absolute term) and “more evolved” (as a comparative term) seem  to be used all-too frequently.  They are uttered not only by non-scientists and […]

BsB in high school science… nice

A  small spike on my blog traffic yesterday led me to look for the source via Google Analytics. (If you are a blogger, you should really use this tool, lots of useful traffic information.) Seems like most of the traffic came from the page of a high school science teacher at Badin High School in […]

Filling in the evolutionary blanks, genome by genome

After hearing Jonathan Eisen and Nikos Kyripdes talk about GEBA in various meetings, it is great to see the paper finally come out, and under a CC license too. Good move for everyone. GEBA is the Genomic Encyclopedia of Bacteria and Archaea. The idea is simple: we have >1000 prokaryotic genomes in GenBank as of […]

The Genomic Ark: 10,000 vertebrate genomes

The first bioinformatics meeting I went to was in 1996 at the  Nachsholim resort,  north of Tel Aviv. I received a fellowship for the duration, and shared a room with the brilliant Golan Yona, then a grad student at the Hebrew University. I was doing biochemistry at the time and knew next to nothing about […]

Weekly poll: Replicators First vs. Metabolism First

I am preparing a class on the origins of life for next week. The textbook I am using does not  go into the Replicators First vs. Metabolism First argument, but I probably will, if I have time. Below, a quick refresher for those who know of the competing theories, and an unsatisfying introduction for those […]

Richard Dawkins and Francis Collins on Colbert Nation

Stephen Colbert had an interesting lineup for the past two nights: Richard Dawkins on Sep 30, and Francis Collins last night. Enjoy the vids: The Colbert Report Mon – Thurs 11:30pm / 10:30c

It ain’t necessarily so

First, a short glossary. Homologous genes are descended from a common ancestral gene. There are two types of homology: Orthology is homology due to a speciation event. So if there is a gene A’ in humans and A” in mice, and they are obviously similar in sequence, we infer that they homologous. We usually also […]

“Micro homology”. Wut?

I ranted in a previous post about the use of homology as a quantitative term, rather than a qualitative term. Ben Blackburne commented on that post introducing me to “micro homology”, a term I did not know existed. I ignored its existence, until I heard it spoken yesterday at a talk, which sort of rubbed […]

Freeloading pays off, but only up to a point.

Quorum sensing Social behavior is not exactly the first term that comes to mind with relation to microbes. After all, we assume a certain amount of intelligence and an ability to implement a behavioral pattern in response to peer actions. Humans, yes. Apes, yes. Birds of a feather flock together… so birds, yes. Ants and […]

A Flurry of Red and Green

UPDATE: I submitted this post to the National Evolutionary Synthesis Center’s sponsored contest for a travel award to ScienceOnline2010. Let’s see how it goes… #scio10 In a previous post about Hatena we saw what might very well be the beginning of a (beautiful?) [:ttip=”symbiosis where one partner lives inside the cell of the other” id=”10″]endosymbiotic[:/ttip] […]

Distant homology and being a little pregnant

(Thanks to F.B.  for the inspiration). Sigh… people don’t seem to learn. It’s been almost 22 years (yikes!) since a distinguished group of scientists published a letter in Cell calling for a responsible use of the word “homology”. If you were born when that letter was published, then in the US you can already drink […]

A Romantic, Maybe too Romantic, Scientist

In the Hatena story about symbiosis, I posted the following picture drawn by Ernst Haeckel: Beautiful!  In this day and age of imaging, high resolution photography, and molecular graphics, we forget that scientific drawing was a skill as necessary to life scientists  as microscopic imaging, or molecular graphics is today.  Indeed, biology was very much […]

From predator to plant in one gulp

The story of a predator that, upon eating a certain food, suddenly becomes a peaceful plant. Sort of. Free-living versus symbiotic A working definition for symbiosis is two or more species that live and interact. Mutualism means that each derives a certain benefit from the other, or at most causing no harm to each other. […]

The Incredible Shrinking Genome

Mass Extinctions and Genomics The geological signs for mass extinctions are very distinct: the photo shows the boundary of the Cretaceous-Tertiary KT extinction that happened ~65 million years ago (Mya), and killed some 70% of the species on Earth, most famously the dinosaurs. This was the last mass extinction, and its effects on Earth’s life […]