A Melting Pot, or Just a Salad? Evaluating Population History Through Gene Flow

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Gene flow is superficially a simple concept; we may liken this evolutionary mechanism to a melting pot. At a fundamental level, when individuals from two defined groups exchange genes, these populations have experienced gene flow. New gene(s) are introduced into one or both populations, and the population becomes more diverse through an increase in genetic variance. When teaching evolution at an introductory level, we generally conclude our explanations at this point.However, identifying gene flow in the past is considerably more difficult.

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Monkey See, Monkey Do? Deciphering the Structure-Function Relationship in the Fossil Record

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An organism’s survival is contingent on the way it moves and interacts with the environment. We can get at the relationship between a living organism’s morphology and the way it moves through direct observation and experimentation. This relationship, however, is more clandestine in fossil organisms. In our last blog post, Ben touched on the use of comparative anatomy to infer the structure-function relationship in the fossil record. In this post, I briefly explore this topic from a historical perspective and discuss its potential for evolutionary analysis. 

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What’s in a Measurement? The Inside (and Outside) Story

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In our last two posts, Kristen and Sam discussed established ways to model the effects of evolutionary forces on skeletal traits. As they both mentioned, we often ask ourselves about whether what we are measuring best represents the traits we’re interested in modeling. At first glance, this may seem to be an esoteric issue, but as I’ll argue here, we should be cautious about measurement choice when we are trying to understand evolutionary change.

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Uncanny Resemblances: When a Heating Coil is like an Adaptive Peak and a Golden Retriever is like Random Genetic Drift

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Some of the most interesting questions in evolutionary biology arise from both unexpected diversity and unexpected similarity among organisms. Sometimes organisms are genetically similar, yet display outward characteristics (phenotypes) that can be strikingly different. Other times, organisms display phenotypes that are astonishingly similar despite greater genetic distances.

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