Teaching Resources: Background Knowledge on Turtle Shell Evolution

Jump to: Palaeontology; Development; Evolution; Ecological Aspects; Useful Diagrams. The turtle’s shell is one of the most striking and unique features found in organismal biology, and questions and debates on its origin have¬†intrigued scientists for¬†more than two centuries, with as much resolution found now as in the 1800s. The turtle …

Phenotypic Plasticity

Some organisms can change their appearance, physiology, and development in response to changes in the environment. This is called phenotypic plasticity, and some examples of phenotypically plastic organisms include the Junonia octavia butterflies described in my natural selection lecture, or water fleas that develop a spiny helmet in the presence …

Fluctuating selection, canalisation, and evolvability: Why macroevolution is not “microevolution writ large”

One of my biggest pet peeves is when people say that macroevolution is just “microevolution writ large”; this is a common saying especially among the creationist-debunkers to counter the claim that microevolution happens but macroevolution doesn’t. It infuriates me to no end, particularly because one of my biggest research goals …

Deep Homology

Darwin referred to the products of evolution as ‘endless forms most beautiful’. Disparity (the word meaning “diversity of morphology”) can be classified: “All mammals have titties” is a valid biological statement. But within all this disparity lie unifying characters: all mammals have boobs, but they also have a backbone; frogs …