The imagery of nature is woven into our language and culture. The moral significance of “going green” or the fear expressed by the term “running wild” are two examples.  It is ironic when we turn our nature-derived concepts to the task of describing nature.  I have been talking about branching rates in many of my… (read more)

I have been working on this post  since 2013. ” I’ll just go to Encyclopedia of Life and count the genera in each of the beetle families”, I said to myself.  If my previous post on the perching birds represented  one neighbourhood in a tidy  little town of  10,000 occupants, the order of beetles is… (read more)

Something remarkable happened 160 million years ago. Three of the most diverse groups on the planet exploded in a simultaneous speciation event.  Two of the groups were new at the beginning of the Cretaceous period, the last chapter in the age of dinosaurs.  Flowering plants had just evolved from conifers and birds had just come… (read more)

Back in May, I said that there was nothing extaordinary about the  maximum rate of branching that occurred early in the evolution of perching birds and that I would show my calculations in my next post.  I want to go to the trouble of backing up my statistics on this so that I can use the… (read more)

The lopsided tendency of evolution to produce many species in one group while preserving just a few in other groups applies quite well to birds. I called this tendency Haldane’s Rule.  Is there something special about groups, like the perching (or Passerine) birds, that dominate our biodiversity?  Or is their diversity a natural outcome from a… (read more)

The peacock’s tail presented a problem for Charles Darwin.  It clearly could not have arisen by natural selection. Its beauty, extravagance, and most of all, its impracticality seemed to argue against the gradual increase, generation after generation, of such a structure within a population. Darwin introduced a separate process, sexual selection, to explain the origin… (read more)

Dr. Pangloss in Voltaire’s Candide is famous for seeing how everything fit perfectly together.  Everything is for the best in the best of all possible worlds!  Most of us have more difficulty in seeing the relationships between living individuals and their environment.  This is especially true when many biological traits or environmental measures are involved. To… (read more)

Natural selection describes how small variations in plants and animals lead to the remarkable fit between their traits and the environments they live in.  It does not, however, always work. The limits to natural selection receive less attention than the potential it has to explain all manner of adaptation and diversity.  I argue here that… (read more)

Biodiversity is one of life’s great perks.  Whether your interests run to gardening, woodworking, wine tasting, or hiking, the variety of life forms all around us enriches and sustains our lives as humans.  The variety in our diets, in the landscapes that surround us, in the medicines that heal us and in the works of… (read more)