Just as we exploit social media to self-promote, find mates, and flaunt social status, animals use visual, olfactory, auditory, or mechanical displays to communicate with one another. Like a Facebook status, these displays often communicate some internal attribute about the organism. A well-known example of this type of signaling is the vibrant tail-feathers of the… Read More I’m looking at the fish in the mirror: a tail of social signaling
Think of a trait, any trait. A bird beak, a butterfly wing, a fish fin. Highly coordinated gene expression networks ultimately produce all traits. Hence, any variation you see in these traits must be due to shifts in gene expression, whether that shift is determined genetically or by some external cue. Evolutionary developmental biologists want… Read More Tiny chompers: How a baby Cichlid behavior influences an adaptive trait
Shrikes are basically nature’s version of Vlad the Impaler. While less gory birds feed on nuts and others peck at insects, shrikes impale their prey onto sharp spikes. Once the unfortunate animal is firmly attached and appropriately subdued, shrikes then tear their prey apart. The result is an array of dismantled corpses of lizards, small… Read More Why the horned lizard has horns: More than a just-so story
Sexual selection has resulted in some of the most flamboyant and outrageous ornaments in the natural world. The flashy plumes of the peacock tail, regal fringe of the lion’s mane, and vibrant colors of the agamid lizard all advertise males’ merits as mates to females. Although sexually selected traits are regularly observed in mammals, birds,… Read More Love stings: Sexual selection on wasp spots
We tend to view sexual selection as secondary to natural selection, but nothing is second to the imperative to reproduce. Sometimes that means that even precisely engineered traits like echolocation have room to be a little sexier. Could falsetto calls really be a signal of male quality in the Mehelyi’s horseshoe bat? … Read More Are male bats actually making echolocation harder to impress the ladies?
Recently, 40+ bird genomes were sequenced, and we are still just beginning to sift through the data. How did birds lose their teeth? (Yes, teeth.) How did they evolve to learn complex songs? Has flying made their genomes smaller? Get the scoop from Allison Schultz. … Read More Bird Genomes: Winging our way
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. … Read More When two become one: the evolution and development of external genitalia on land