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March 29, 2013

Persistent polymorphisms, enhancing mutation, new fossils, cooperation & conservation

All five of my Darwinian Agriculture lectures at the International Rice Research Institute are now available on YouTube.

Here are some interesting papers published this week.

Multiple Instances of Ancient Balancing Selection Shared Between Humans and Chimpanzees " In addition to the major histocompatibility complex, we identified 125 regions in which the same haplotypes are segregating in the two species [neither version has displaced the other in either species in 6 million years], all but two of which are noncoding [i.e., they probably control other genes rather than coding for a protein]." The most likely explanation for such prolonged co-existence is that individuals with less-common alleles may be resistant to pathogens that have evolved to attack those with more-common alleles.

Accelerated gene evolution through replication-transcription conflicts" "We propose that bacteria, and potentially other organisms, promote faster evolution of specific genes through orientation-dependent encounters between DNA replication and transcription."

Palaeontology: Tubular worms from the Burgess Shale"

Preservation of ovarian follicles reveals early evolution of avian reproductive behaviour"

Both information and social cohesion determine collective decisions in animal groups

Governance regime and location influence avoided deforestation success of protected areas in the Brazilian Amazon

Wild Pollinators Enhance Fruit Set of Crops Regardless of Honey Bee Abundance

March 23, 2013

Darwinian Agriculture at the International Rice Research Institute

I'm at the International Rice Research Institute (IRRI) in the Philippines this week, for a series of lectures on my book, Darwinian Agriculture. IRRI is posting my talks on YouTube. For links, and some notes on my discussions with IRRI staff, see my Darwinian Agriculture blog.

March 18, 2013

More conference spam... from Nature

I've complained in the past about fake scientific conferences organized by BIT Life Sciences and IEEE. Now Nature Publishing Group is getting into the act, with TEDMED:

"meet a Nobel laureate or two, talk informally with the heads of the FDA, NIH..."
If I did medical research, I might be fooled into thinking the invitation had something to do with my expertise. The $4950 registration fee gives the game away, though.

March 15, 2013

This week's picks

I'm off to the International Rice Research Institute to give a series of five lectures on Darwinian Agriculture. Here are some papers that look interesting this week.

Adaptive Evolution of Multiple Traits Through Multiple Mutations at a Single Gene
Hind Wings in Basal Birds and the Evolution of Leg Feathers
Lifespan of neurons is uncoupled from organismal lifespan
Naturally occurring allele diversity allows potato cultivation in northern latitudes"
Water-controlled wealth of nations

March 8, 2013

Cooperation, inducible defense, cancer, and more

Here are some papers that look interesting this week.

Prairie Dogs Disperse When All Close Kin Have Disappeared "cooperation among kin is more important than competition among kin for young prairie dogs"

Variants at serotonin transporter and 2A receptor genes predict cooperative behavior differentially according to presence of punishment "Participants with a variant at the serotonin transporter gene contribute more, leading to group-level differences in cooperation, but this effect dissipates in the presence of punishment."

Plant mating system transitions drive the macroevolution of defense strategies
the repeated, unidirectional transition from ancestral self-incompatibility (obligate outcrossing) to self-compatibility (increased inbreeding) leads to the evolution of an inducible (vs. constitutive) strategy of plant resistance to herbivores."

Intratumor heterogeneity in human glioblastoma reflects cancer evolutionary dynamics "we reconstructed the phylogeny of the fragments for each patient, identifying copy number alterations in EGFR and CDKN2A/B/p14ARF as early events, and aberrations in PDGFRA and PTEN as later events during cancer progression"

Non-optimal codon usage is a mechanism to achieve circadian clock conditionality"
"natural selection against optimal codons to achieve adaptive responses to environmental changes"

Gene Transfer from Bacteria and Archaea Facilitated Evolution of an Extremophilic Eukaryote "> 5% of protein-coding genes of G. sulphuraria were probably acquired horizontally"

Recent land use change in the Western Corn Belt threatens grasslands and wetlands
"a recent doubling in commodity prices has created incentives for landowners to convert grassland to corn and soybean cropping... onto marginal lands characterized by high erosion risk and vulnerability to drought."

March 1, 2013

Copying in birds, dolphins, and viruses; evolution & environmental change; evolution of mutation rate

Learning and signal copying facilitate communication among bird species "where only two species regularly interact, one species' [alarm] calls incorporate the call of the other."

Vocal copying of individually distinctive signature whistles in bottlenose dolphins "Copying occurred almost exclusively between close associates such as mother-calf pairs and male alliances during separation... copies were clearly recognizable as such because copiers consistently modified some acoustic parameters of a signal when copying it... no evidence for the use of copying in aggression or deception."

A bacteriophage encodes its own CRISPR/Cas adaptive response to evade host innate immunity "the only documented bacterial adaptive immune system is the CRISPR/Cas... a phage-encoded CRISPR/Cas system is used to counteract a phage inhibitory chromosomal island of the bacterial host. "

Evolutionary rescue from extinction is contingent on a lower rate of environmental change" "By assessing fitness of these engineered [E. coli] strains across a range of drug concentrations, we show that certain genotypes are evolutionarily inaccessible under rapid environmental change."

Fossil evidence for a hyperdiverse sclerophyll flora under a non-Mediterranean-type climate "sclerophyll hyperdiversity has developed in distinctly non-Mediterranean climates... likely a response to long-term climate stability."

A trade-off between oxidative stress resistance and DNA repair plays a role in the evolution of elevated mutation rates in bacteria "The dominant paradigm for the evolution of mutator alleles in bacterial populations is that they spread by indirect selection for linked beneficial mutations when bacteria are poorly adapted... [but] hydrogen peroxide, generates direct selection for an elevated mutation rate in the pathogenic bacterium Pseudomonas aeruginosa as a consequence of a trade-off between the fidelity of DNA repair and hydrogen peroxide resistance."