Cretaceous crab revolution

The Cretaceous crab revolution refers to a major diversification event of brachyuran crabs (also known as true crabs) that took place during the Cretaceous Period, from 145 to 66 million years ago.[1][2] Nearly 80% of modern groups of crabs originated during this event.[3] The Cretaceous crab revolution is a smaller component of the greater Mesozoic marine revolution.[4]

Early diversification edit

The oldest known true crabs are Eoprosopon klugi and Eocarcinus praecursor from the Early to Middle Jurassic.[5][6] While that fossil crab, and a few other Jurassic species, establish that crabs existed in older time periods, crabs did not truly diversify into numerous species until the beginning of the Cretaceous.[3] During this time, crabs evolved into many different body plans and lifestyles, including the carcinized body shape like that of blue crabs that many people are familiar with.[7][8] At the same time, many families of crabs evolved away from the carcinized body plan, termed decarcinization.[1][2] The Cretaceous crab revolution also witnessed the evolution of more unusual body forms in crabs, including the enigmatic Callichimaera perplexa.[1] This rapid diversification allowed true crabs to inhabit many different environments including fresh water environments, coral reefs, swimming within the water column, and many others.[3] Cretaceous crabs exhibit expert shell-breaking behavior with powerful claws (the left claw is smaller than the right) (Dietl & Vega, 2008).

References edit

  1. ^ a b c Luque, J.; Feldmann, R. M.; Vernygora, O.; Schweitzer, C. E.; Cameron, C. B.; Kerr, K. A.; Vega, F. J.; Duque, A.; Strange, M.; Palmer, A. R.; Jaramillo, C. (April 2019). "Exceptional preservation of mid-Cretaceous marine arthropods and the evolution of novel forms via heterochrony". Science Advances. 5 (4): eaav3875. Bibcode:2019SciA....5.3875L. doi:10.1126/sciadv.aav3875. ISSN 2375-2548. PMC 6482010. PMID 31032408.
  2. ^ a b Luque, Javier; Bracken-Grissom, Heather; Ortega-Hernandez, Javier; Wolfe, Joanna (2019). "Phylogenetics of true crabs, and the early origins of crab-like forms" (PDF). The Palaeontological Association (PalAss) Annual Meeting.
  3. ^ a b c Schweitzer, Carrie E.; Feldmann, Rodney M. (2015-08-27). "Faunal turnover and niche stability in marine Decapoda in the Phanerozoic". Journal of Crustacean Biology. 35 (5): 633–649. doi:10.1163/1937240x-00002359. ISSN 0278-0372.
  4. ^ Vermeij, G.J. (1977). "The Mesozoic marine revolution: evidence from snails, predators and grazers". Paleobiology. 1977 (3): 245–258. doi:10.1017/S0094837300005352. S2CID 54742050.
  5. ^ Schweitzer, Carrie E.; Feldmann, Rodney M. (2010-05-01). "The Oldest Brachyura (Decapoda: Homolodromioidea: Glaessneropsoidea) Known to Date (Jurassic)". Journal of Crustacean Biology. 30 (2): 251–256. doi:10.1651/09-3231.1. ISSN 0278-0372. S2CID 84707572.
  6. ^ Scholtz, Gerhard (2020-11-01). "Eocarcinus praecursor Withers, 1932 (Malacostraca, Decapoda, Meiura) is a stem group brachyuran". Arthropod Structure & Development. 59: 100991. doi:10.1016/j.asd.2020.100991. ISSN 1467-8039. PMID 32891896. S2CID 221525257.
  7. ^ Borradaile, L.A. (1916). "Crustacea. Part II. Porcellanopagurus: An instance of carcinization, in British Antarctic ("Terra Nova") Expedition, 1910". Zoology. 3: 111–126.
  8. ^ Scholtz, Gerhard (2014-03-26). "Evolution of crabs – history and deconstruction of a prime example of convergence". Contributions to Zoology. 83 (2): 87–105. doi:10.1163/18759866-08302001. ISSN 1875-9866.


Dietl, G. P., & Vega , F. J. (2008, March 10). Specialized shell-breaking crab claws in cretaceous seas | biology ... Biology Letters. https://royalsocietypublishing.org/doi/abs/10.1098/rsbl.2008.0031