Category: Phylogenetics

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Phylogenetic Trees and the Climate-Niche Evolution of Leaf-Warblers

By: Emily Desrosiers, Molly Nyhan, and Tyler Umbra (Stonehill College, BIO323: Evolution, Spring 2026)

In the forests of Europe and Asia, there is a group of small, greenish birds called leaf-warblers. These birds look physically identical to the average person as well as many experts. For years, they have been an evolutionary puzzle: how do species that look so similar end up living in such vastly different environments?

To answer questions like these, researchers make use of phylogenetic trees—diagrams that show how different groups of living things are related and from whom they evolved. If we can trace the ancestry of a bunch of these leaf-warblers, surely, we can get a picture of how and when they spread across vast distances, right? This is where the work of Gräf et al. (2025) comes in, with their recent article published in the journal Diversity, titled “Climate-Niche Evolution in Leaf-Warblers (Aves: Phylloscopidae): A Matter of Phylogeny”.

A short podcast summarizing the article. Image of Tickell’s Leaf Warbler by Earthshine: https://commons.wikimedia.org/wiki/File:Tickell%27s_Leaf_Warbler.JPG
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Exploring the evolution of aestivation in turtles: unraveling the relation between their morphological traits with their aestivation time

By: Elizabeth Parkinson, Madison Barrett, Nathanaelle Brignol, and Robert Branco
(Stonehill College, BIO323: Evolution, Spring 2023)

Overview

Hibernation, or winter dormancy, is a well-known biological process. It is well represented in different forms of media and cultural traditions, such as children’s books and Groundhog Day. However, aestivation, or summer dormancy, is a lesser-known biological process. Similar to hibernation, organisms that undergo aestivation experience a state of decreased physiological activity over a prolonged period. It is considered by many scientists to be a strategy for surviving hot and dry seasons when water is hard to come by, and it is carried out by many species of reptiles and amphibians, among other classes of animals. A research article titled, “How Aestivation Evolved in Turtles: A Macroevolutionary and Morphological Approach,” explores how this trait evolved in many different species of turtless. It also studies the link between the length of aestivation undergone by a turtle and the structure of that turtle’s shell. They found that rather than occurring in a single ancestral species to all turtles, aestivation independently evolved in two different turtle clades. They also found that shell structure is related to aestivation time in varying ways across different families of turtles. This result indicates that a turtle’s environment may also influence their aestivation time.  To learn more about aestivation in turtles, read more below, or listen to our podcast above!

A short podcast summarizing the article. Image credit: https://study.com/academy/lesson/estivation-definition-examples.html
Continue reading “Exploring the evolution of aestivation in turtles: unraveling the relation between their morphological traits with their aestivation time”