A is for Algae

I got my copy of Jillian Freese’s A is for Algae earlier this week. Freese, a Ph.D. candidate at the University of Rhode Island, says the book is “Part birthday gift. Part #scicomm. Part stress relief.” It’s full of watercolor paintings of algae, mostly seaweeds but with some phytoplankton as well. Each species (one for each letter of the alphabet) is presented with its scientific name, usually a common name, habitat and biogeographic information, and some interesting factoids.A is for Algae

Warning: spoilers below the fold.

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Postdoc opportunity studying Volvox!

If I were a graduate student nearing graduation, I would apply for this: an NSF-funded postdoc opportunity in the Umen lab at the Donald Danforth Plant Science Center in St. Louis.

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Everything Flows

Everything Flows cover

Process philosophy has really just recently come on my radar, and I’m not sure what to make of it. I have written before that I don’t have a particularly strong background in philosophy, and so I’m hesitant to judge what I may not understand. At least some of the descriptions I’ve seen strike me as quasi-mystical word salads:

In short, a becoming actual entity prehends, or “feels,” not only other, past actual entities (which may be seen as the metaphysical basis for causality wherein one entity becomes part of another entity’s formation process), but also eternal objects (i.e., “pure possibilities”), which introduces novelty into the process. –Lukasz Lamza in Nature Alive – Essays on the Emergence and Evolution of Living Agents

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You misspelled “Irresponsible reporting”

Earlier this week, Tom Sheldon caused a flurry when he published an opinion piece in Nature:

Sheldon header

While the article casts preprints, preprint servers, and scientists who post their work to preprint servers as potential sources of misinformation, its arguments better support the case that science reporters should act more responsibly. Full disclosure: as a scientist who posts [some of] their work to a preprint server, I have a horse in this race.

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Elephants and oak trees

The Major Transitions in Evolution cover

The increase [in complexity] has been neither universal nor inevitable. Bacteria, for example, are probably no more complex today than their ancestors 2000 million years ago. The most that we can say is that some lineages have become more complex in the course of time. Complexity is hard to define or to measure, but there is surely some sense in which elephants and oak trees are more complex than bacteria, and bacteria than the first replicating molecules.

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Uncommon Descent on Elizabeth Pennisi’s Science article

Two-headed quarter

Image from www.twoheadedquarter.net.

Yesterday, I ran a bit long about Elizabeth Pennisi’s new article in Science, “The momentous transition to multicellular life may not have been so hard after all.” I’m not the only one who noticed it, though; Uncommon Descent also commented (“At Science: Maybe the transition from single cells to multicellular life wasn’t that hard?“). There’s not much to it, just a longish quote from the article followed by this:

So at the basic level, there is a program that adapts single cells to multicellularity? Yes, that certainly makes multicellularity easier and even swifter but it also make traditional Darwinian explanations sound ever more stretched.

So if the evolution of multicellularity is easy, that’s evidence against “traditional Darwinian explanations.” Remember “Heads I win, tails you lose“?

…if multicellularity is really complicated, that’s evidence for intelligent design. But if multicellularity is really simple, that’s evidence for intelligent design.

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Multicellularity in Science

I spent the last week of June backpacking in Baxter State Park, Maine. When I finally emerged from the woods, my first stop was Shin Pond Village for a pay shower, a non-rehydrated breakfast, and free internet access. Among the week’s worth of unread emails were a nice surprise and a not-so-nice surprise. The not-so-nice surprise was a manuscript rejected without review; the nice surprise was a new article by Elizabeth Pennisi in Science, which came out when I was somewhere between Upper South Branch Pond and Webster Outlet.

Upper South Branch Pond

Upper South Branch Pond, Baxter State Park, Maine. I spent two nights here.

The article, for which I was interviewed before Baxter, synthesizes recent work across a wide range of organisms that suggests that the evolution of multicellularity may not be as difficult a step as we often assume:

The evolutionary histories of some groups of organisms record repeated transitions from single-celled to multicellular forms, suggesting the hurdles could not have been so high. Genetic comparisons between simple multicellular organisms and their single-celled relatives have revealed that much of the molecular equipment needed for cells to band together and coordinate their activities may have been in place well before multicellularity evolved. And clever experiments have shown that in the test tube, single-celled life can evolve the beginnings of multicellularity in just a few hundred generations—an evolutionary instant.

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Pierre Haas & Stephanie Höhn article on variability in Volvox inversion

Back in September, I reported on an arXiv preprint by Pierre Haas, Stephanie Höhn, and colleagues*, “Mechanics and variability of cell sheet folding in the embryonic inversion of Volvox.” A revised version of that manuscript has now been published in PLoS Biology (“The noisy basis of morphogenesis: Mechanisms and mechanics of cell sheet folding inferred from developmental variability”).

Haas et al. 2018 Fig. 3

Figure 3 from Haas, Höhn, et al. 2018. Inverting Volvox globator embryo visualised by selective plane illumination microscopy of chlorophyll autofluorescence. Top row: maximum-intensity projection of z-stacks. Bottom row: tracing of midsagittal cross-sections; the colour scheme indicates image intensity. Scale bar: 50 μm.

Inversion is a crucial process in the development of algae in the family Volvocaceae (which includes Colemanosphaera, Eudorina, Pandorina, Platydorina, Pleodorina, Volvox, Volvulina, and Yamagishiella), because they start off inside-out, with their flagella pointing inward. Inversion gets the flagella on the outside where they are useful for propulsion.

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Technical problem: bad link

WordPress has a “publicize” function that automatically sends an email and posts to social media when I publish a new blog post. Unfortunately, the email and social media posts accompanying my last blog post linked to the wrong post (not even one of mine; it’s a decade-old post by PZ Myers). The correct link is https://freethoughtblogs.com/fierceroller/?p=4606.

I’m going to go ahead and guess that the link for this post is wrong, too; it should be https://freethoughtblogs.com/fierceroller/?p=4612. Hopefully Freethought Blogs will get this fixed soon.