Assorted Darwin Day Content

For this year's Darwin Day post, I will highlight a number of items I have recently run across on Twitter. Some of these have been retweeted on the Orthogonal Research and Education Lab Twitter feed, other materials are related to discussions in our research group meetings.

To start things off, I will draw your attention to a new special issue of Royal Society of London B called "Basal cognition: multicellularity, neurons and the cognitive lens" that is worth checking out. The term "basal" refers to evolutionary origins in the context of phylogeny (the tree of life). 

There are three papers of particular note for Darwin Day: "The chemical brain hypothesis for the origin of nervous systems" by Gaspar Jekely, "Elementary Nervous Systems" by Detlev Arendt, and "Uncovering cognitive similarities and differences, conservation and innovation" by Michael Levin and colleagues.

The new paper on elementary nervous systems in Royal Society B (click to enlarge, figure from paper). COURTESY: Detlev Arendt.

A pointer to the Darwin Online repository.

In terms of old drawings and other archival materials, check out the Darwin Online project. This is a nice repository of Darwin-related historical and scientific works. This resource contains books, personal correspondence, and published materials. Speaking of history, let's turn to the deep history of life.....

A billion years of continental drift as an animated gif. Click to enlarge.

This next feature is a new paper on a billion years of plate tectonic dynamics: "Extending full-plate tectonic models into deep time: Linking the Neoproterozoic and the Phanerozoic" by Mike Tetley and colleagues. Now published in Earth Science Reviews, it is something we recently discussed in the weekly DevoWorm group meeting.

Following up on the DevoWorm discussion, which was about mapping the continental drift animation to the most basal branches of the tree of life, is an attempt to map Mammalian phylogeny [1] to continental drift over the past 225 million years. This was created by Carlos E. Alvarez. The numbers on the maps (top) correspond to the numbered clades (subtrees - bottom). This topic deserves a deeper dive into the latest Phylogeography research [2], which may be the subject of a future blog spot.

An attempt at matching up the tree of life with continental drift (click to enlarge). COURTESY: Carlos E. Alvarez

The next feature is a new paper on evolution of development (evo-devo) in nervous system anatomy called "Evolution of new cell types at the lateral neural border", now published in Current Topics in Developmental Biology. This study even uses converging evidence from genetic regulatory networks and anatomy to demonstrate common mechanisms shared between invertebrates and vertebrates.

A new paper on the evolution of new neuronal cell types (click to enlarge). COURTESY: Jan Stundl (Caltech).

Not only is this Darwin Day, but also the 50th anniversary of a Nature paper by Kimura and Ohta [3] on the Neutral Theory of Molecular Evolution. Neutral Theory postulates that most biological variation is expressed in selectively neutral genes, and so is random in nature [4]. This stands in opposition to the selectionist perspective of evolutionary change [5, 6].

Fully-tweetable neutral theory of evolution. COURTESY: Andrew J. Crawford.

Finally, and returning to neuroevolution, there are several items of interest from the laboratory of Cassandra Extavour. The first is a talk at the Society of Integrative and Comparative Biology meeting on the evo-devo-eco-neuro-biology of Drosophila learning and memory. For more evo-devo work from Dr. Extavour's lab, check out this recent work (with open data) on insect size and shape [7, 8].

Original artwork from SICB Twitter Account, commentary from Ken A. Field.

Hand-drawn notes on the SICB plenary talk. COURTESY: Dr. Ajna Rivera.

NOTES:

[1] Foley N.M., Springer M.S. and Teeling E.C. (2016). Mammal madness: is the mammal tree of life not yet resolved? Philosophical Transactions of the Royal Society B, 37120150140. doi:10.1098/ rstb.2015.0140.

[2] Avise, J.C. (2000). Phylogeography: the history and formation of species. Harvard University Press, Cambridge, MA.

[3] Kimura, M. and Ohta, T. (1971). Protein Polymorphism as a Phase of Molecular Evolution. Nature, 229, 467–469.

[4] Kimura, M. (1983). The Neutral Theory of Molecular Evolution. Cambridge University Press, Cambridge, UK.

[5] Nei, M. (2005). Selectionism and Neutralism in Molecular Evolution. Molecular Biology and Evolution, 22(12), 2318–2342. doi:10.1093/molbev/msi242.

[6] There are other critiques of selectionism from other perspectives. Here is one in the area of brain function: Fernando, C., Szathmary, E., and Husbands, P. (2012). Selectionist and Evolutionary Approaches to Brain Function: A Critical Appraisal. Frontiers in Computational Neuroscience, 6, 24. doi:10.3389/ fncom.2012.00024.

[7] Church, S.H., Donoughe, S., de Medeiros, B.A.S., and Extavour, C.G. (2019). Insect egg size and shape evolve with ecology but not developmental rate. Nature, 571, 58–62.

[8] Church, S.H., Donoughe, S., de Medeiros, B.A.S., and Extavour, C.G. (2019). A dataset of egg size and shape from more than 6,700 insect species. Scientific Data, 6, 104.