Friday coffee break

Caffeine molecule

The caffeine molecule: more important to science than ethidium bromide?

Every Friday at Nothing in Biology Makes Sense! our contributors pass around links to new scientific results, or science-y news, or videos of adorable wildlife, that they’re most likely to bring up while waiting in line for a latte.

From Devin: A new study finds that two genetic markers associated with increased risk of breast and ovarian cancer are also associated with greater fertility.

Individuals who tested positive for BRCA1/2 mutations who linked into multi-generational pedigrees within the Utah Population Database were used to identify putative obligate carriers. We find that women born before 1930 who are mutation carriers have significantly more children than controls and have excess post-reproductive mortality risks. They also have shorter birth intervals and end child-bearing later than controls.

From Jon: An amendment to the Mississippi state constitution (and similar ones in other states) would confer legal “personhood” on fertilized eggs, a move with wide-reaching implications for women’s reproductive freedom, medicine, and basic scientific research.

The amendment in Mississippi would ban virtually all abortions, including those resulting from rape or incest. It would bar some birth control methods, including IUDs and “morning-after pills,” which prevent fertilized eggs from implanting in the uterus. It would also outlaw the destruction of embryos created in laboratories.

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New papers from NiB contributors

White sands, New Mexico

White gypsum sands: officially an ecological opportunity

Evidently they’re not willing to toot their own horns, so I’ll do it on their behalf: Two of our contributors, Simone Des Roches and Chris Smith, have brand-new publications in print, and both papers are open access, available to anyone who wants to take a look.

Simone’s paper makes the case that the gypsum sands of White Sands, New Mexico, create an “ecological release” for lizards living there, since reduced predator density and diversity on the white dunes lets the lizards use a wider range of habitat types, and achieve higher population density.

First, we provide evidence for ecological opportunity by demonstrating reduced species richness and abundance of potential competitors and predators at White Sands relative to nearby dark soils habitats. Second, we characterize ecological release at White Sands by demonstrating density compensation in the three White Sands lizard species and expanded resource use in White Sands Sceloporus undulatus.

Chris’s paper tests the hypothesis that Joshua trees have expanded their range northward since the last glacial maximum, drawing together many different data sets to find the same signal of population expansion.

Using a database of >5000 GPS records for Joshua trees, and multi-locus DNA sequence data from the Joshua tree and four species of yucca moth, we combined paleaodistribution modeling with coalescent-based analyses of demographic and phylgeographic history. We extensively evaluated the power of our methods to infer past population size and distributional changes by evaluating the effect of different inference procedures on our results, comparing our palaeodistribution models to Pleistocene-aged packrat midden records, and simulating DNA sequence data under a variety of alternative demographic histories.

Double, double toil and trouble: a tale of two infections

Wordle of text from Ben-Ami et al 2011

What are the evolutionary consequences of parasite superinfection (i.e. simultaneous infection by multiple parasites)? When parasites are genetically distinct, coexistence within a host generates conflict because of limited resources. How this conflict is resolved is the source of evolutionary research on the evolution of parasite life history traits such as virulence, the negative effects on the host caused by infection, and transmission mode, how parasites infect a new host. The transmission mode of a parasite is often characterized as occurring in one of two different modes: vertical or horizontal. With vertical transmission, an offspring obtains its parasites directly from its parents. In contrast, with horizontal transmission, infections occur either directly from the environment or contagiously by infection from other individuals.

My interest in the evolution of transmission mode in parasites and symbionts led me to a recent paper (Ben-Ami et al. 2011), which addresses the consequences of superinfection by two different parasites with different transmission modes of the waterflea, Daphnia magna, on virulence and parasite fecundity. Pasteuria ramosa is a castrating, horizontally transmitted, blood-infecting bacterium where spores are produced from the cadaver of the host Daphnia. Octosporea bayeri, a microsporidium, utilizes both vertical transmission to eggs and horizontal transmission via waterborne spores.

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CreatureCast: Strangler figs

Kevin Zelnio’s post about the need for evolutionary biologists to approach outreach like viral marketing reminded me about CreatureCast, a frickin’ awesome project by the Dunn Lab at Brown University, which has scientists talking about their work in bite-sized videos illustrated with whimsical animation. Here’s one on strangler figs:

If this isn’t a good argument for adding a little money to your next grant to support an undergrad video production or communication major as a “broader impact,” I don’t know what is.

(Cross-posted from Denim and Tweed)

Friday coffee break

Experimental coffee

NiB does not endorse drinking coffee at your lab bench. No, sir.

Every Friday at Nothing in Biology Makes Sense! our contributors pass around links to new scientific results, or science-y news, or videos of adorable wildlife, that they’re most likely to bring up while waiting in line for a latte.

From Devin: The National Science Foundation explains broader impacts, the part of NSF grant applications intended to connect basic research with society beyond the lab.

“So many people have interpreted the broader-impacts criterion as requiring something involving K-12 education,” says Cora Marrett, deputy NSF director and former head of NSF’s education directorate. “But that’s not our position at all.”

From Jon: A breast cancer pathologist learns she has breast cancer.

“There’s never a good time to have cancer,” she said. But this was clearly one of the worst. She was working full time, having recently been named director of breast pathology at the University of Washington Medical Center in Seattle.

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Science-y picture of the *random time interval*!

“We will call phoresy all phenomena of transport in the strict sense, that is, those cases in which the transport host serves its passenger only as a vehicle”

-Pierre Lesne (1896)

This is a photo of a crane fly (Tipulidae) with three pseudoscorpions (a type of Arachnid) holding on to its thorax.  This has been observed frequently, and it is thought that the pseudoscorpions are merely attempting to hitch a ride, a behavior known as phoresy.  Where they are hoping to go is beyond me, but the fly was overburdened and flying erratically, so they probably didn’t make it far.  The photo was taken in Clark Creek Natural Area, Mississippi.