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May 31, 2013

This week's picks

Functional Extinction of Birds Drives Rapid Evolutionary Changes in Seed Size "areas deprived of large avian frugivores for several decades present smaller seeds than nondefaunated forests, with negative consequences for palm regeneration"

Molecular evolution of peptidergic signaling systems in bilaterians "phylogenetic reconstruction tools... show that a large fraction of human PSs [peptide-based signaling systems] were already present in the last common ancestor of flies, mollusks, urchins, and mammals"

Honey constituents up-regulate detoxification and immunity genes in the western honey bee Apis mellifera "apicultural use of honey substitutes, including high-fructose corn syrup, may thus compromise the ability of honey bees to cope with pesticides and pathogens and contribute to colony losses"

Palaeontological evidence for an Oligocene divergence between Old World monkeys and apes" "the oldest known fossil 'ape', represented by a partial mandible... the oldest stem member of the Old World monkey clade, represented by a lower third molar... recovered from a precisely dated 25.2-Myr-old stratum in... the East African Rift in Tanzania."

Experimental evidence that evolutionarily diverse assemblages result in higher productivity "Species produced more biomass than predicted from their monocultures when they were in plots with distantly related species and produced the amount of biomass predicted from monoculture when sown with close relatives."

May 24, 2013

Put MOOCs to the test

With all the hoopla about whether universities should give academic credit for what students learn in online courses (MOOCs), people seem to be missing the point that we already have a widely-accepted mechanism by which students can get credit for material learned elsewhere: the Advanced Placement (AP) tests. If MOOCs are doing such a great job, why aren't they publicizing AP-test success rates for their students?

No, seriously. I'm open to the hypothesis that a student could learn as much or more in a well-produced MOOC than in a typical large-lecture/computer-graded introductory course. But let's see the data.

Professor Char Weise writes:

"I am also a parent who is going to be paying college tuition for his oldest child in a couple of years. I am being made keenly aware of the cost-quality tradeoff, and I'm seeing a product that sacrifices only a little on the quality end while having major benefits on the cost end. As a parent, I'm intrigued. As a professor at a liberal arts college, I am terrified."
...and suggests...

"Another approach would be to outsource the introductory courses in economics and other disciplines [to MOOCs]. We already do this to some extent by accepting credit for our introductory courses for courses taught at high schools or other institutions including community colleges. A student who gets a score of 5 on the AP economics test gets credit for Econ 103 and 104... I can imagine a time when the standard program of higher education involves a student spending a year (maybe less) accumulating a year's worth of college credit for introductory courses by taking MOOCs and then enrolling in Gettysburg's (or a similar institution's) excellent and prestigious three-year bachelors' program."
Outsourcing introductory classes, which few professors enjoy teaching, would free us to teach more-interesting, advanced classes. Offering credit for MOOCs on advanced topics without a widely-accepted standard test is more problematic than continuing to offer credit for high AP-test scores. If we had data showing that grades in introductory MOOCs were highly predictive of AP-test scores, that would give me some confidence in their grading, but advanced classes typically call for reasoning and analysis skills that are harder to test. Also, advanced classes are more likely to benefit from small-group interactions with the professor. Take Bill Hamilton, for example. (You knew there had to be an evolution angle here somewhere!) According to this excellent biography by Ullica Segerstrale, he was a terrible lecturer in introductory classes, but did a great job on smaller advanced classes.

May 17, 2013

Cooperation => deception?

Cooperation creates selection for tactical deception [Open Access] "cooperation can create selection pressures favouring the evolution of... deception weakening cheater detection in conditional cooperators"
They present a model and supporting data showing a positive correlation between cooperativeness and deception in nonhuman primates. With a broader definition of deception, this could apply to species without brains. For example, rhizobia bacteria that simply fail to provide their legume hosts with nitrogen get hit with plant sanctions that reduce their fitness, but rhizobia that interfere with a plant's internal signaling can get away with cheating.

Also this week:

Nanoscale analysis of pyritized microfossils reveals differential heterotrophic consumption in the ∼1.9-Ga Gunflint chert "Three-dimensional nanotomography reveals additional pyritized biomaterial, including hollow, cellular epibionts and extracellular polymeric substances, showing a preference for attachment to Gunflintia over Huroniospora and interpreted as components of a saprophytic heterotrophic, decomposing community. " 1.9-billion-year-old fossils? Isn't that 1.899994 billion years before the earth was created?

Adaptive dynamics under development-based genotype-phenotype maps"
Evolution: Stuck between the teeth"
"developmental complexity often prevents natural selection from reaching optimal fitness when fitness is directly linked to attaining a particular phenotype, but that these 'adaptive peaks' can be reached when fitness is instead linked to functional properties of the phenotype.

May 3, 2013

Sampling Daphnia from a canoe, in the snow, May 3...

...for our research on the evolution of aging. Sandra Brovold is sampling, I'm trying to remember the J stroke, and Bob Sterner took the video.

May 1, 2013

Handwritten data to CSV file without typing

Tired of typing data from lab notebooks into spreadsheets?

* Record data using a Livescribe pen, in one of their microdot notebooks.
* Put a comma after each entry, including last entry in each line.
* Use MyScript to convert page to text, using Rich Text option.
* Select (highlight) table data, including comma-separated heading.
* Open a blank Libre-Office Calc (spreadsheet) document.
* Edit / Paste Special, using "Unformatted text'' and comma-separated options.
* Edit if needed.
* Save as .CSV file using defaults.

The result can be opened in Excel, if you insist. When I tried pasting the data directly into Excel, values weren't separated properly, but there may be a way to do it.

I have only tested this with Livescribe 4 GB Echo Smartpen.

I got this idea here.