We don’t know about you, but we’re sleeping off the aftereffects of too much pumpkin pie, and then we need to strategize some holiday shopping. See you next week!
Here’s what we’ll be talking about while we wait in line for a latte.
From CJ: Slowing cricket calls down to the frequency range of human voices makes for some trippy tones. And it looks like a virus that has been killing hundreds of dolphins off the U.S. east coast may be striking whales, too.
From Amy: DNA from the body of a boy who died during the last ice age includes markers linked to modern European and American Indian populations.
From Jeremy, a whole raft of stuff this week about antibiotic use and abuse: U.S. states with higher rates of antibiotic prescription have more obesity. The evolution of antibiotic-resistant bacteria could dramatically restrict modern medicine. Here’s what working physicians are doing to prevent that.
Here’s what we’ll be talking about while we’re waiting in line for a latte. And maybe some pie?
And finally, via Robert Krulwich, here’s why there’s always a ring around your glass of wine.
In a pretty interesting example of cross fertilization between scientific disciplines, a recently published paper by Jashmid Tehrani uses phylogenetic methods borrowed from evolutionary biology to construct an “evolutionary tree” of fables related to Little Red Riding Hood.
Tales typical of Riding Hood are found mostly in Europe, but a series of stories sharing some features are found in Africa (involving an Ogre) and East Asia (The Tiger Grandmother). These have sometimes been considered to be part of the Riding Hood group, but there has been debate over whether or not they actually belong to another, closely related group found in Europe and the Middle East known as The Wolf and the Kids.
This week we have a guest post by Jessica Oswald a graduate student at the Florida Museum of Natural History at the University of Florida. She works on the biogeography of neotropical birds using fossil, ecological, and molecular genetic data.
As an avian paleontologist, digging through fossils is to me like birding with a time machine. These fossils help us paint a picture of where modern forms came from and how different ancient species were from modern-day birds, especially intermediate forms. These outliers and in-betweeners are interesting because they hint at all sorts of morphological diversity that we don’t even know or expect, and give us a window into the past and how different diversity, communities, and climatic conditions and landscapes were from what we are familiar with today.
This paper (Ksepka et al. 2013) on an early bird in the Swift-hummingbird clade does both of these things by exhibiting an odd morphology that we don’t see in modern birds, and helps us understand how the uniquely specialized wing shapes in modern swifts and hummingbirds arose from their common ancestor.
Members of the order Apodiformes: treeswifts (Hemiprocnidae), true swifts (Apodidae), and hummingbirds (Trochilidae), are aerial marvels. Swifts are able to reach the highest speeds during level flight (Chantler 1999) and hummingbirds are well known for their hovering abilities and their sideways and backward flight. Swifts and hummingbirds, while sharing the same wing bone characteristics, have different lengths of flight feathers, resulting in different wing shapes across the group, which allows them to perform their different aerial feats. Hummingbirds have shorter wings relative to their body size compared to swifts, resulting in their hovering abilities. These different wing shapes are well suited for their modern functions, but we have almost no fossils from this group, so we don’t know how the wing shapes diverged, or anything about the ecology of ancient species in this lineage.
Here’s what we’ll be talking about while we’re waiting in line for a latte:
From Amy: Want to feel less bad about that experiment that just exploded? Wash you hands of that failure.
Evolution by natural selection is not usually considered very peaceful—the “survival of the fittest” is usually assumed to come at the expense of competitors for food or shelter or other resources. But the “fittest” can also be those who recruit assistance from other individuals, or other species—and who provide assistance in return.
This was the perspective of Peter Kropotkin, a Russian prince and political anarchist who studied the wildlife of Siberia while working as an agent of the Czar’s government. In the harsh conditions of the Siberian winter, Kropotkin reported finding not a bitter struggle over scarce resources, but what he called “Mutual Aid” among species, as well as in the human settlements that managed to eke out a living.
Something like what Kropotkin described is documented in a new paper by Elizabeth Pringle and colleagues. Examining a protection mutualism between ants and the tropical Central American tree Cordia alliodora, Pringle et al. found that drier, more stressful environments supported more investment in the mutualism.