Nothing in Biology Makes Sense: Dispersal versus mutation, on the edge

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Cane Toad at Daintree Village A cane toad, living in an evolutionary “Olympic village”? Photo by tubagooba.

This week at Nothing in Biology Makes Sense!, Devin Drown explains the population dynamics that crop up near the edge of a species’s geographic range:

One famous example of this phenomenon is found among invasive cane toads (Rinella marina) in Australia. In 2006, Phillips et al found that the toads at the leading edge of the expansion had longer legs making them primary candidates for high dispersal capabilities. Later, Lindstrom et al (2013) found (via radio collar measurements) that those toads at the front of the range were more likely to disperse than those at the encamped within the population.

To find out why biologists have compared life on the range edge to living in the athletes’ dormitory at the Olympics, go the whole thing.◼

Science online, moral hazards edition

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Coffee cup Off to the races. Photo by @Doug88888.

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Conscience, and objections

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A wilderness firefighting crew of conscientious objectors in 1945, who were clearly doing it all wrong. (WikiMedia Commons)

There’s an emerging strain of thought in contemporary, politicized U.S. Christianity, which holds that freedom of religion logically must permit pharmacists to refuse to fill prescriptions for birth control pills if they believe that birth control is wrong; or, more lately, for people who provide wedding-related services to refuse to serve gay or lesbian couples if they oppose same-sex marriage. These refusals of service are an expression of conscience, the reasoning goes, and you can’t just force someone to violate their conscience, even if it’s in the course of doing their job.

This thinking would have come as quite the surprise to the Christian tradition in which I was raised. Mennonites know something about conscientious objection, since they’re pacifists—so, rather than take up arms, my grandparents’ generation spent the Second World War doing alternative, nonviolent service in forestry and soil conservation, in public health and psychiatric care, as wilderness fire fighters, and even as human guinea pigs. That is to say, they felt it was wrong to kill, so they opted to do hard, unpleasant, even quite dangerous things rather than take a job that required them to kill.

But clearly what those COs should actually have done was sign right up for the draft, work their ways through boot camp, ship out to the front—and then lay down their arms. From what I can tell, the current generation of “dissenters” would say it was only a free exercise of their Constitutional rights.◼

The Molecular Ecologist: The 2014 Next-Generation Sequencing Field Guide

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Alineando secuencias (1) Photo by Shaury.

One of the most popular items at The Molecular Ecologist isn’t a blog post—it’s Travis Glenn’s “Field Guide” to the capabilities and costs of the many next-generation sequencing technologies currently available. Today we’re pleased to release the 2014 update to the Guide, this time with some new personal insight from Travis in the form of both an introductory blog post and a new table rating the overall quality of each technology:

Overall, if you are in the market for a next generation DNA sequencer in early 2014, the data indicate one clear inexorable trend – think Illumina. For fans of the Brady Bunch – Illumina, Illumina, Illumina! For fans of Star Trek – Prepare to be assimilated by one of Illumina’s Borg-like cubes. For fans of Henry Ford – You can have any NSG instrument you want, so long as it’s an Illumina.

Travis’s post is well worth reading in full, and you’ll want to update your bookmarks to the new comparison tables.◼

One of these moths is not like the other … but does that matter to Joshua trees?

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A Joshua tree flower, up close
A Joshua tree flower, up close

Cross-posted from Nothing in Biology Makes Sense!

A huge diversity of flowering plants rely on animals to carry pollen from one flower to another, ensuring healthy, more genetically diverse offpsring. These animal-pollinated species are in a somewhat unique position, from an evolutionary perspective: they can become reproductively isolated, and form new species, as a result of evolutionary or ecological change in an entirely different species.

Evolutionary biologists have had good reason to think that pollinators often play a role in the formation of new plant species since at least the middle of the 20th century, when Verne Grant observed that animal-pollinated plant species are more likely to differ in their floral characteristics than plants that move pollen around via wind. More recently, biologists have gone as far as to dissect the genetic basis of traits that determine which pollinator species are attracted to a flower—and thus, which flowers can trade pollen.

However, while it’s very well established that pollinators can maintain isolation between plant populations, we have much less evidence that interactions with pollinators help to create that isolation in the first place. One likely candidate for such pollinator-mediated speciation is Joshua tree, the iconic plant of the Mojave Desert.

Continue reading →

Science online, gold-star creationist edition

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Tomatoes You might want to plant your own tomatoes, this year. Photo by rachelandrew.

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The Molecular Ecologist: Reviewing the causes of population genetic structure

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distance Photo by eliassss.

At The Molecular Ecologist today, I highlight a couple of recent literature reviews that seek to understand how natural populations are structured by the limitations of distance, and by local adaptation:

Taken together, these two papers are a nice compilation of a very large literature. If nothing else, they demonstrate that we’re well past the point of asking whether environmental isolation happens at all—in fact, it looks to be quite common—and we’re ready to start digging into the details of when and why it develops.

To see what broad patterns two different groups of authors were able to extract from their surveys of many population genetic studies, go read the whole thing.◼

Nothing in Biology Makes Sense: Can a creationist be a (public university) biology lecturer?

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2010.02.15 - Life Sciences South The Life Sciences building at the University of Idaho. Photo by jby.

Over at Nothing in Biology Makes Sense! I’m confronting my discovery that the University of Idaho, where I received my Ph.D., has hired an outspoken proponent of young-Earth creationism to teach its introductory microbiology course this semester:

I can, at least in principle, imagine a creationist professor who taught the contents of a microbiology curriculum, complete with the common descent of life on Earth, and never breathed a word of his personal beliefs in the classroom. Could Gordon Wilson—of all people—be that “gold-star” creationist?

I decided the only way to answer that question was to ask Gordon Wilson.

Wilson, you may recall, appeared on D&T before, many moons ago. To find out what he had to say for himself, go read the whole thing.◼

Muse

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Actually, I don’t think I want a Muse of fire.

Fire is finicky, hard to get started,
Especially when the wood is wet.
And then it burns too hot, and consumes everything.

None of this is helpful when you’re on deadline.

I’d really rather have a Muse of electricity.
Sparking with sharp, blue wit,
Casting bright, fluorescent light on all its subjects,
Summoned at the tap of my keyboard.◼

Science online, one in twenty edition

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One in a billion Photo by Micah Sittig.

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