My Year of Darwin 10/31/2014: Darwin's Tree of Life

"so by generation I believe it has been with the great Tree of Life, which fills with its dead and broken branches with crust of the earth, and covers the surface with its ever branching and beautiful ramifications." 

Charles Darwin, Origin of Species 1st edition (on Kindle)

I find this beautiful and apropos for today's lecture on phylogenetics. 

What I'm teaching this week

• Evolution and Population Biology

Started teaching it yesterday. Looks like a good class of some 60 students.

• Species Concepts (yesterday)
• Basics of Phylogenetics: what is phylogenetics, interpreting trees

I'm a systematist-wannabe and hoping to get more training during a sabbatical, which I'm due for.

• Biostatistics
• Poisson and Negative Binomial (yesterday)
• Zero-inflated versions of those (ZIP and ZINB)
• Intro to logistic regression 

My Year of Darwin 10/30/2014: Creationism doesn't explain the hierarchical nature of life

"On the view that each species has been independently created, I can see no explanation of this great fact in the classification of all organic beings; but, to the best of my judgement, it is explained through inheritance and the complex action of natural selection" Charles Darwin, Origin of Species 1st edition (on Kindle)

Darwin is pointing out that creationism cannot explain why most of life can be arranged hierarchically - species into genera, genera into families, families into orders, and so on. In arguments, I've heard creationists say that this points to a single creator. But why? 

My Year of Darwin 10/29/2014: Yup, we're all related

"It is a truly wonderful fact - the wonder of which we are apt to overlook from familiarity- that all animals and all plants throughout all time and space should be related to each other in group subordinate to group, in the the manner which we everywhere behold..." Charles Darwin, Origin of Species 1st edition (on Kindle)

We, all of life on this planet, are just buds on the tips of branches on the same tree of life. We are all the survivors and it is beautiful. 

My Year of Darwin 10/28/2014: There must be some beneficial mutations

"I think it would be a most extraordinary fact if no variation ever had occurred useful to each being's own welfare." Charles Darwin, Origin of Species 1st edition (on Kindle)

I heard it leveled by creationists that no beneficial mutations have ever been documented. Logically this seems absurd if we consider that the environment is constantly changing and if organisms were created perfectly for their environment then they must change (the population - not any particular individual) to persist in a new environment. 

Snowy Egret from Forsythe National Wildlife Refuge (aka Brigantine)

My Year of Darwin 10/27/2014: No crystal ball for evolution

"Looking to the future, we can predict that the groups of organic beings which are now large and triumphant, and which are least broken up, that is, which as yet have suffered least extinction, will fora long period continue to increase. But which groups will ultimately prevail, no man can predict." Charles Darwin, Origin of Species 1st edition (on Kindle)

Stephen J. Gould was fond of saying that if we could rewind the tapestry of life it would replay differently. I concur. Contingencies are part of everyday life and a part of the larger world that plays out across the planet.

Great Egret from Chincoteague Island