External genitalia are an important adaptation to life on the land, where eggs may dry out and there is no water for sperm to swim through. Reptiles, birds, and mammals have extremely diverse external genitalia, but they share a common evolutionary and developmental origin. Mara Laslo explains how comparative developmental studies are shedding insight on the development of these remarkable organs.
The dog is the only large carnivore that has been fully domesticated and one the few domesticated animals that was not kept primarily for food. Despite their widespread adoption into human cultures today, relatively little is known about the early events in the history of dog domestication. When and where did dogs originally become domesticated? Russ Corbett-Detig explains.
By David Fronk 1, 2, 3, shoot! Joe threw paper, Jane scissors, and you stuck with trusty rock. For the umpteenth time, you repeat the ritual in the hopes someone will deviate from their norms and break the cycle. 1, 2, 3, shoot! Same results. With each of you competing against each other, the stalemate … Continue reading Real-life rock-paper-scissors
Frivolous as it may sound to us, making pretty flowers is serious business for a plant. Fancier flowers often mean more attention from pollinators and greater reproductive success, and the huge diversity of flowers around today shows that the evolution of new flower types has paid off. But how can plants afford to experiment with such an important developmental process? As Becky Povilus explains, they do and they don't.
The orb-weaving spiders build webs so spectacular and bizarre that it seemed they must also be one-of-a-kind. As Tauana Junqueira Cunha explains, modern phylogenetic techniques have now unraveled a tangled web of data to reveal the true story.
We aren't even sure if they are really alive, but, as Maryam Chaib de Mares explains, the distribution of viruses across the three domains of life (Bacteria, Archaea, and Eukarya) may reflect how viruses have shaped the evolution of cellular life.
You might have thought eusociality, an extreme form of cooperation that makes a colony of individuals verge on a superorganism, was just for ants and bees. As we learn more natural history, though, we see more and more examples. Here, Jack Boyle explains how scientists created artificial nests so they could observe the social habits of X. saxesenii, an ambrosia beetle normally concealed in tree trunks, to determine whether they meet the three eusociality criteria.