It gets better

So, I know I’m on hiatus for a little, but this is pretty important. Following news of yet another gay teen bullied into committing suicide, Dan Savage had a revelation:

… I wish I could have talked to this kid for five minutes. I wish I could have told Billy that it gets better. I wish I could have told him that, however bad things were, however isolated and alone he was, it gets better.

But gay adults aren’t allowed to talk to these kids. Schools and churches don’t bring us in to talk to teenagers who are being bullied. Many of these kids have homophobic parents who believe that they can prevent their gay children from growing up to be gay—or from ever coming out—by depriving them of information, resources, and positive role models.

Why are we waiting for permission to talk to these kids? We have the ability to talk directly to them right now. We don’t have to wait for permission to let them know that it gets better. We can reach these kids.

So here’s what you can do, GBVWS: Make a video. Tell them it gets better.

So Dan launched the It Gets Better Project over on YouTube, starting with a video in which he and his husband describe how it got better for them. The project is looking for more submissions.

Totally swamped

Fellowship proposal writing, teaching, research, job hunting. No sign yet of the rodents of unusual size, but they’re coming up later in the semester for my mammalogy students, if I remember the curriculum correctly. Much as I hate to watch my pageview count decay, I’m suspending regular posting until I get back onto solid ground.

Science online, chaste and helpful siblings edition

First, the meta-news: Months ago now, Pepsigate drove some of the leading lights of ScienceBlogs in search of new homes, and with new developments this week most of them now have. Mostly this has been through the formation of brand-new science blogging networks, which are snapping up more than just the SB Diaspora. GrrlScientist and The Lay Scientist have been at Guardian Science blogs for awhile now; PLoS launched PLoS Blogs with Deborah Blum, Steve Silberman, and the Obesity Panacea guys among others. Now Wired Science has brought in Brian Switek, Mary McKenna and David Dobbs to join Jonah Lehrer and others in their new network, and Bora Zivkovic has accepted a well-deserved position as Community Editor for the Scientific American blog network. If you’re having as much trouble keeping up with all this as I am, here’s a nice graphical explanation [PDF].

A cooperative-breeding pied babbler. Photo by Blake Matheson.

Now, on to the science:

  • Effort where effort is due. A new analysis finds that tigers might be most effectively conserved by focusing efforts on just six percent of their current habitat. (Conservation Magazine)
  • When it rains, it pours. The ongoing human-driven extinction of worldwide diversity may not be greater than past mass extinctions, but it’s happening a lot faster. (Gravity’s Rainbow)
  • Must. Resist. Urge to. Anthropomorphize. An analysis of hundreds of bird species suggests that cooperative breeding behavior—where offspring stick around to help raise their siblings—is associated with lower promiscuity. (It Takes 30)
  • Trust me, it’ll make your life better. Get that dissertation published! (Open Source Paleontologist)
  • Not when I’m getting up for a 6 a.m. run, it isn’t. Two experiments with rats provide evidence that endurance exercise can be addictive. (DrugMonkey)
  • See a little farther. The 27th edition of The Giant’s Shoulders history of science blog carnival is out this week at Entertaining Research.
  • Maybe standing on those shoulders made you dizzy? The 2nd edition of the Carnal Carnival is online, hosted by Dr. Carin Bondar. This edition’s carnality: barf.

And now, Richard Attenborough presents flying squirrels:

Scientia Pro Publica 39, now online at Punctuated Equilibria

Photo by Jacques Marcoux.

The 39th edition of Scientia Pro Publica, the blog carnival for lay-level science writing, went up yesterday at Punctuated Equilbria, with a nice companion post by host GrrlScientist on the utility and philosophy of blog carnivals in general. My recent post on specialization in mutualism versus antagonism is included in a long list of interesting links.

What keeps mutualists honest—cake, or death?

This post was chosen as an Editor's Selection for ResearchBlogging.orgSomewhat like cooperation between members of the same species, mutually beneficial interactions between different species should be prone to fall apart when one species evolves a way to cheat the other. Biologists who study mutualism (myself included) have long believed that the solution to cheating is to punish cheaters—but a new model suggests that the benefits gained from playing nice might be enough to deter cheating [PDF].

I knew I had to write about this one when I saw that the authors use their model to propose a new explanation for the dynamics of my own favorite mutualism, between yuccas and yucca moths. (And, yes, it’s also an excuse to reference Eddie Izzard. I’m only human.)

Cake: definitely preferable to death. Photo by 3liz4.

The new analysis by Weyl et al. applies an economic modeling framework to species interactions in which one species provides some benefit to another, and then itself receives a benefit that at least partially derives from the help initially provided. To take one example the authors cite, many ant species colonize acacia plants, which grow structures in which the ants can nest (or domatia), and often produce nectar or other food rewards for the ants. The ant colony defends the plant from insect herbivores, with the consequence that the plant can devote more energy to growth, including new domatia and new leaves to fuel nectar production via photosynthesis.

In many such interactions, it’s been thought that each species can only keep the other from cheating—taking the benefits of the relationship without returning the favor—by actively punishing such behavior. Weyl et al. argue that instead of punishment, cheaters might be deterred if their refusal to play their role results in reduced payback from the other partner.

In the ant-acacia example, ant-tended plants kill off branches that lose a lot of leaves to herbivores, which can happen if the ants cheat by slacking off on their protection duties. But this isn’t punishment as such, say Weyl et al. Plants that aren’t protected by ants also kill off damaged branches, to conserve resources. Instead, because ant domatia tend to be located on the youngest, most herbivore-vulnerable shoots of ant-tended plants, lazy ants harm themselves by allowing herbivores to trigger a response that the plant would make whether or not it hosted ants.


An ant domatium on a “whistling thorn” acacia tree. Photo by Alistair Rae.

It sounds a bit passive-aggressive on the plant’s part, doesn’t it? But let’s look at the example that caught my attention: yuccas and yucca moths. Yucca moths are the sole pollinators of yuccas, and lay their eggs in pollinated yucca flowers; as a pollinated flower develops into a fruit, the eggs hatch, and the new-born larvae eat some of the seeds inside. Moths have good incentive to cheat on yuccas by laying lots of eggs in a single flower or not providing much pollen, but yuccas abort flowers that receive too many moth eggs, or not enough pollen [PDF]. Those of us who study yuccas have tended to interpret this as punishment, since killing off a pollinated flower also kills off any seeds a yucca might have produced via that flower.

However, as Weyl et al. note, yuccas abort flowers in response to damage to the floral ovules [PDF] (the tissue that will become seeds when pollinated), not to the presence of moth eggs per se. Moths generally damage the ovules a bit when laying eggs inside the flowers; but damage without eggs has the same effect. If floral abortion were punishment, say Weyl et al., it would occur as a result of moth eggs alone, not damage to the ovules in general.

In other words, the mutualists analyzed by this new paper are kept honest not by the threat of punishment (death) but the possibility that cheating will result in reduced rewards (less cake). It’s a clever inversion of perspective, and I’ll be very interested to see whether new empirical studies can back it up.

References

Marr, D., & Pellmyr, O. (2003). Effect of pollinator-inflicted ovule damage on floral abscission in the yucca-yucca moth mutualism: the role of mechanical and chemical factors. Oecologia, 136 (2), 236-43 DOI: 10.1007/s00442-003-1279-3

Pellmyr, O., & Huth, C. (1994). Evolutionary stability of mutualism between yuccas and yucca moths. Nature, 372 (6503), 257-60 DOI: 10.1038/372257a0

Weyl, E., Frederickson, M., Yu, D., & Pierce, N. (2010). Economic contract theory tests models of mutualism. Proc. Nat. Acad. Sci. USA, 107 (36), 15712-6 DOI: 10.1073/pnas.1005294107

Science online, where have all the taxonomists gone? edition

Cool ant! Anyone know what species it is? Anyone? Bueller? Photo by ViaMoi.
  • Subversive science under Stalin’s mustachioed nose. Artificial selection for human-friendly behavior in foxes on a Russian fur farm also led to physical changes. (Jason Goldman, guest-writing for Scientific American)
  • Cast off for Science! Dr. Bik of Deep Sea News will be sailing the Gulf of Mexico to study the effects of the recent oil spill on biodiversity there, thanks to new NSF funding—and blogging the whole way. (Deep Sea News)
  • Wii should really play outside instead. The physical benefits of video “exergames” may be overrated. (Obesity Panacea)
  • Is your car turned off? Turn it off again. Deborah Blum sets a new stylistic standard for science blogs with a cautionary tale of carbon monoxide poisoning. (Speakeasy Science)
  • Well, to be fair, they’re really nerdy. Morphology-based identification of species is still important, but no-one wants to actually employ taxonomists these days. (Myrmecos)
  • Toad versus ants. Invasive ants introduced to the Indonesian island of Sulawesi seem to have met their match in a native, ant-eating toad. (Wired Science)
  • So that’s what it takes to gross out a lizard. Crickets defend themselves against predators by vomiting and hemorrhaging on cue. (Carin Bondar)
  • I, for one, welcome our new orca overlords. Killer whales have learned how to hunt and kill great white sharks. (Deep Sea News)

This week’s video was going to be the one about shark-eating whales, until someone decided to illustrate Tom Lehrer’s “Elements” using Google’s shiny new instant-response search. I have my priorities.

I have writing to do

And not for this venue. I will, however, take the time to note that the works of Leroy Anderson seem to be unusually good at maintaining my concentration while I work. Exempli gratia:

Please feel free to use the comments to tell me what a profoundly boring person I am.

Getting out of their depth: How rockfish speciate without physical barriers

ResearchBlogging.orgMost evolutionary biologists believe that the easiest means for two populations to become reproductively isolated—a first step to splitting into different species—is a physical barrier to movement. Mountain ranges, deep river valleys, or the sheer distance between an island and the mainland—the opportunities for allopatric speciation are all over the place. Unless, of course, you remember that the planet’s largest habitat is the ocean, and there aren’t such obvious physical barriers out at sea.

How do fish and other marine organisms form new species, then? Maybe they’re more likely to speciate as a result of natural selection that varies among otherwise connected marine habitats. For instance, a new study of rockfish finds evidence that this new species in this group usually form by adapting to conditions found at different oceanic depths [$a].


Two rockfish species, Sebastes atrovirens and Sebastes chrysomelas. Photos by brian.gratwicke.

The rockfish genus Sebastes contains several dozen species, but many of them occur in about the same regions of the Pacific ocean. Rather than being separated by physical distance, the group has diversified into different ecological niches, from the intertidal zone down to depths of 600 meters. The new study’s author, Travis Ingram, wanted to determine whether these habitat differences or geographic distance has more often been the cause of rockfish speciation, which he did using two major analyses.

In the first, Ingram asked whether pairs of rockfish species were more or less likely to occupy the same latitudes, and the same depth ranges, as they diverged over time. Allopatric speciation would lead to closely-related rockfish species occupying separate latitude ranges, but Ingram found the opposite. On the other hand, closely-related rockfish species are less likely to live at the same depth in the ocean—so depth, not geographic distance, seems to be important in rockfish speciation.

Ingram’s second analysis takes advantage of the general principle that traits associated with forming new species should change relatively rapidly at about the same time as speciation events, rather than at a uniform rate over time. Traits that undergo this speciational evolution can be distinguished from traits that don’t based on the relationship between trait values of related species. The idea is to compare the trait values for pairs of species drawn from the group of interest—if the differences in trait values are more strongly correlated with the number of speciation events that have occurred since the pair of species last shared a common ancestor than with the raw time since that common ancestry, the trait has probably evolved in speciational fashion.

This is the pattern Ingram found in the depths occupied by different species of rockfish. Changes in depth range occupied by rockfish were associated with speciation events, rather than evolving steadily over time. How these changes could have contributed to reproductive isolation is another question—different depth habitats present rockfish with different kinds of predators and prey, but also with different light environments for visual mating signals. One or more of these environmental differences could create the sort of divergent natural selection that can lead to reproductive isolation and speciation.

Reference

Ingram, T. (2010). Speciation along a depth gradient in a marine adaptive radiation. Proc. Royal Soc. B : 10.1098/rspb.2010.1127

Barack Obama’s (lack of) moral leadership

My Sunday morning reading includes a trenchant essay by Jacob Weisberg at Slate, which gathers together President Obama’s disappointing performances on immigration, freedom of religion, and gay marriage under the rubric of moral cowardice:

Obama has had numerous occasions to assert leadership on values issues this summer: Arizona’s crude anti-immigrant law, the battle over Prop 8 and gay marriage, and the backlash against what Fox News persists in calling the “Ground Zero mosque.” These battles raise fundamental questions of national identity, liberty, and individual rights. When Lindsey Graham argues for rewriting the Constitution to eliminate the birthright citizenship clause of the 14th Amendment, or Newt Gingrich proposes a Saudi standard for the free exercise of religion, they’re taking positions at odds with America’s basic ideals. But Obama’s instinctive caution has steered him away from casting these questions as moral or civil rights issues. On none of them has he shown anything resembling courage. [links sic]

To Weisberg’s list, I’d also add the need for comprehensive, carbon-limiting energy legislation. Treating undocumented immigrants like human beings, Muslim and gay Americans like citizens, climate change as a genuine impending human-created disaster—these are all inherently moral positions. Liberals have long been sick of watching that morality overruled by the weird, selfish, other-hating morality of contemporary American conservatism. I voted for Barack Obama (and I think lots of us did) because he seemed likely to articulate liberal beliefs in explicitly moral language, and do it with conviction.

Remember his campaign speech on race? With his feet to the media fire over his apparently scandalous association with Jeremiah Wright, Obama acknowledged the subtleties and complications of our national racial history, without losing sight of basic principles of right and wrong:

The profound mistake of Reverend Wright’s sermons is not that he spoke about racism in our society. It’s that he spoke as if our society was static; as if no progress has been made; as if this country—a country that has made it possible for one of his own members to run for the highest office in the land and build a coalition of white and black; Latino and Asian, rich and poor, young and old—is still irrevocably bound to a tragic past.

That’s the Barack Obama I wanted to be President. I could’ve sworn I voted for that one. But it doesn’t seem to be the guy who ended up in office.

Candidate Obama at a rally in Pittsburgh, 21 April 2008. Photo by BarackObama.com.