Treefinder retracted


Remember the flap about a German scientist restricting the license to his software (Treefinder) to protest European immigration policies? Not a great idea if your software is published in an open access journal.

Gangolf Jobb cut off licensing of his program to European countries he considered too welcoming to immigrants. Last week, BMC Evolutionary Biology published a retraction of the 2004 article that introduced Treefinder, citing their policy on software availability:

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(Probably not) Precambrian Volvox

A new(ish) paper in National Science Review evaluates the evidence for various interpretations of Ediacaran microfossils from the Weng’an biota in South China (Xiao et al. 2014. The Weng’an biota and the Ediacaran radiation of multicellular eukaryotes. Natl. Sci. Rev., 1:498–520.). I recommend checking it out; it’s open access, and there’s a lot of interesting stuff in there that I’m not going to address.

These fossils are undoubtedly multicellular, probably eukaryotic, and extremely enigmatic. Their age (582-600 million years) means they could have important implications for the evolution of multicellularity, and their exceptional preservation in great numbers creates the potential for reconstructing their life cycles in great detail. Some of the Weng’an fossils have been interpreted as volvocine algae, an interpretation that I find highly unlikely.

Some of the Weng’an fossils are thought to represent red algae, and this would not be terribly surprising, since red algae have been around for at least 1.2 billion years. Others, for example the tubular fossils, are more problematic, with interpretations as diverse as cyanobacteria, eukaryotic algae, crinoids, and cnidarians.

Fig. 8 from Xiao et al. 2014

Figure 8 from Xiao et al. 2014: Schematic diagram showing diagnostic features of the five recognized species of tubular microfossils in the Weng’an biota.

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Actin evolution in the Volvocales

Kato-Minoura Figure 1

Fig. 1 from Kato-Minoura et al. 2015: Genomic structure of volvocine actin and NAP genes. For comparison, previously identified sequences are also shown. Filled boxes, putative coding exons; open boxes, putative 5′ and 3′ untranslated regions. Intervening sequences are shown by solid lines. Intron positions are indicated by codon and phase numbers with reference to the three alpha-actins of vertebrates (377 amino acids) (Weber and Kabsch 1994). The conserved intron positions are linked with dotted lines. ATG, translation start codon; TAA or TGA, stop codon.

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New Scientist article on experimental evolution of multicellularity

On the second day of AbSciCon, members of the Ratcliff lab and I met with a reporter, Bob Holmes, from New Scientist. We had all given our talks on the first day of the meeting. The resulting article came out yesterday.

I’ve dealt with New Scientist before, and I find them among the better science news outlets. They make a real effort to understand the science behind their stories, a refreshing change from sites that slap misleading headlines onto barely reworded university press releases. Aaaand I’m going to wrap this up before it turns into a rant.

Peter Conlin, Jennifer Pentz, Bob Holmes, and Will Ratcliff

Peter Conlin, Jennifer Pentz, Bob Holmes, and Will Ratcliff enjoying some sushi in a Chicago park.

Pleodorina study featured on NAI website

My new paper in Evolutionary Ecology Research is currently featured on the NASA Astrobiology Institute website (“Algae Fitness and Multicellular Life“). This was the final chapter of my Ph.D. dissertation, and it describes an artificial selection experiment using Pleodorina starrii. The paper is co-authored by my Ph.D. advisor, Rick Michod, and two (then) undergraduates, Susma Ghimire and Conner Vinikoor.
Pleodorina starrii

A 32-celled colony of Pleodorina starrii with 12 somatic cells.

Pleodorina is considered “partially differentiated,” meaning that some of its cells are of the ancestral, undifferentiated type (like those of Eudorina) and some are differentiated as somatic cells. These somatic cells never grow much, and they never divide to form daughter colonies.

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The most important time in your life

The New York Times has picked up a recent article in Physical Review Letters by Stephanie Höhn and colleagues (Höhn, S., Honerkamp-Smith, A.R., Haas, P. a., Trong, P.K. and Goldstein, R.E. 2015. Dynamics of a Volvox embryo turning itself inside out. Phys. Rev. Lett., 114: 1–5. doi 10.1103/PhysRevLett.114.178101).

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