Colonies
Experimental Snowball Earth Viscosity Drives the Evolution of Motile Multicellularity
February 8, 2024Halling, A., Goodson, B., Hirschmann, A., Wing, B. A., and Simpson, C., 2024. Experimental Snowball Earth Viscosity Drives the Evolution of Motile Multicellularity. bioRxiv. doi.org/10.1101/2024.02.06.579218 pdf During the 70-million-year span of the Cryogenian Snowball Earth glaciations, low ocean temperatures beneath global sea ice increased water viscosity up to fourfold. In...
Physical constraints during Snowball Earth drive the evolution of multicellularity
December 10, 2023Crockett, W.W., Shaw, J.O., ** Simpson, C.**, and Kemps, C.P. 2023. Physical constraints during Snowball Earth drive the evolution of multicellularity. bioRXiv doi.org/10.1101/2023.12.07.570654 pdf Molecular and fossil evidence suggest that complex eukaryotic multicellularity evolved during the late Neoproterozoic era, coincident with Snowball Earth glaciations, where ice sheets covered most of...
Aggregate Trait Evolvability and Macroevolution in Two Sister Species of the Bryozoan *Stylopoma*
November 27, 2022Leventhal, S., Jamison-Todd, S., and Simpson, C., 2022. Aggregate Trait Evolvability and Macroevolution in Two Sister Species of the Bryozoan Stylopoma, Evolutionary Biology. doi.org/10.1007/s11692-022-09588-8 pdf The study of trait evolution in modular animals is more complicated than that in solitary animals, because a single genotype of a modular colony can...
Bryozoan revelations
March 30, 2022Simpson, C. and J. B. C. Jackson, 2022. Bryozoan Revelations, Science Advances. 8 (13), eabp9344. dooi:10.1126/sciadv.abp9344 Bryozoans, simple invertebrates living on the sea floor, are emerging as a model system for understanding ecological and evolutionary processes on macroevolutionary scales.
Adaptation to a viscous Snowball Earth Ocean as a path to complex multicellularity
May 16, 2021Simpson, C. (2021) Adaptation to a viscous Snowball Earth Ocean as a path to complex multicellularity. American Naturalist. link Animals, fungi, and algae with complex multicellular bodies all evolved independently from unicellular ancestors. The early history of these major eukaryotic multicellular clades, if not their origins, co-occur with an extreme...
From the individual to the colony: marine invertebrates as models to understand levels of biological organization
March 20, 2021Laurel Sky Hiebert, Leandro M. Vieira, Stefano Tiozzo, Carl Simpson, Richard K. Grosberg, Alvaro E. Migotto, Andre C. Morandini, Federico D. Brown Simpson, C. (2021) From the individual to the colony: marine invertebrates as models to understand levels of biological organization. Journal of Experimental Zoology Part B: Molecular and Developmental...
An ecological driver for the macroevolution of morphological polymorphism within colonial invertebrates
May 13, 2020Simpson, C. (2020) An ecological driver for the macroevolution of morphological polymorphism within colonial invertebrates. Journal of Experimental Zoology Part B: Molecular and Developmental Evolution. DOI: 10.1002/(ISSN)1552-5015 Colonial marine invertebrates, such as corals and bryozoans, have modular growth. Individual modules within a colony are homologous to an individual solitary animal...
Coloniality, clonality, and modularity in animals: The elephant in the room
April 29, 2020Hiebert, Laurel S., Carl Simpson, and Stefano Tiozzo. Coloniality, clonality, and modularity in animals: The elephant in the room. Journal of Experimental Zoology Part B: Molecular and Developmental Evolution (2020). Nearly half of the animal phyla contain species that propagate asexually via agametic reproduction, often forming colonies of genetically identical...
How colonial animals evolve.
September 18, 2019Simpson, Carl, Amalia Herrera-Cubilla, and Jeremy BC Jackson. “How colonial animals evolve.” Science Advances 6, no. 2 (2020): eaaw9530. The evolution of modular colonial animals such as reef corals and bryozoans is enigmatic because of the ability for modules to proliferate asexually as whole colonies reproduce sexually. This reproductive duality...
Bryozoan basics
November 7, 2016Bryozoans are a phylum of colonial animals. They first appear in the fossil record during the early Ordovician (~480 million years ago.) Since that time, bryozoans have been a major component of the fossil record and of marine communities. Their colonies are modular, with individual animals, called zooids, forming the...
Evolutionary determinants of morphological polymorphism in colonial animals
April 20, 2016Simpson, C., Jackson, J. B. C., Herrera-Cubilla, A. 2017. Evolutionary determinants of morphological polymorphism in colonial animals. American Naturalist. 190(1): 17-28. link Preprint version available at bioRxiv doi: http://dx.doi.org/10.1101/046409 pdf Colonial animals commonly exhibit morphologically polymorphic modular units that are phenotypically distinct and specialize in specific functional tasks. But how...
The evolutionary history of division of labour
April 10, 2015Simpson, C. 2012. The evolutionary history of division of labour. Proceedings of the Royal Society B: Biological Sciences 279:116–121. pdf Functional specialization, or division of labour (DOL), of parts within organisms and colonies is common in most multi-cellular, colonial and social organisms, but it is far from ubiquitous. Several mechanisms...
Evolutionary diversification of reef corals--a comparison of the molecular and fossil records
April 7, 2015Simpson, C., Kiessling, W., Mewis, H., Baron-Szabo, R. C. & Müller, J. 2011. Evolutionary diversification of reef corals: a comparison of the molecular and fossil records. Evolution. 65(11) 3274–3284. DOI: 10.1111/j.1558-5646.2011.01365.x pdf Understanding historical patterns of diversity dynamics is of paramount importance for many evolutionary questions. The fossil record has...
The Miscellaneous Transitions in Evolution
April 5, 2015McShea, D. W. & Simpson, C. 2011. The Miscellaneous Transitions in Evolution. In, The Major Transitions Revisited, Brett Calcott & Kim Sterelny eds. MIT Press. pdf In Mark Twain’s Letters from the Earth, his sardonic alter ego Puddin’head Wilson reflects that if the Eiffel Tower represented the history of the...
How many levels are there?
April 5, 2015Simpson, C. 2011. How many levels are there? How insights from evolutionary transitions in individuality help measure the hierarchical complexity of life. In, The Major Transitions in Evolution Revisited, Brett Calcott & Kim Sterelny eds. MIT Press. pdf How the vast range of spatial and temporal scales on which biological...
On the potential for ocean acidification to be a general cause of ancient reef crises
April 4, 2015Kiessling, W. & Simpson, C. 2011 On the potential for ocean acidification to be a general cause of ancient reef crises. Global Change Biology. 17(1): 56 - 67. doi: 10.1111/j.1365-2486.2010.02204.x pdf Anthropogenic rise in the carbon dioxide concentration in the atmosphere leads to global warming and acidification of the oceans....
Reefs as Cradles of Evolution and Sources of Biodiversity in the Phanerozoic
April 3, 2015Kiessling, W., Simpson, C. & Foote, M. 2010 Reefs as Cradles of Evolution and Sources of Biodiversity in the Phanerozoic. Science 327(5962): 196-198. pdf Large-scale biodiversity gradients among environments and habitats are usually attributed to a complex array of ecological and evolutionary factors. We tested the evolutionary component of such...
How similar are branching networks in nature?
April 1, 2015Sánchez, J. A., Lasker, H. R., Zeng, W., Coluci, V. & Simpson, C. 2003 How similar are branching networks in nature? A view from the ocean: Caribbean gorgonian corals. Journal of Theoretical Biology 222, 135-138. pdf Tree-like branching networks are omnipresent in nature (eg Turcotte et al., 1998). Despite the...
Expansion and the hierarchical structure of levels of selection
September 21, 2013Evolutionary success comes to the selfish—or so most biologists are taught. Those organisms that reproduce most will of course be better represented in future generations. Current theory has had great success using this fact to understand much of evolution, but it hits a wall when it comes to understanding how...