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Sally Shelton
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Family legacy challenge week 1: What is your name?
What is your full name? Explain why your parents gave you that name. I'm starting the challenge at Family Legacy: check it out at  https://familysearch.org/blog/en/52-questions-52-weeks/ . They claim that this is the easiest way to write your life story. We...
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Evidence of maternal care in 500 million year old extinct crustacean
Waptia fieldensis WA an extinct crustacean that lived more than five hundred million years ago. Discovery of well preserved fossils of five specimens show evidence of brood care. It carried 24 eggs in crevice of its body.
Waptia and the Diversification of Brood Care in Early Arthropods
http://goo.gl/faE2cn
Summary Brood care, including the carrying of eggs or juveniles, is a form of parental care, which, like other parental traits, enhances offspring fitness with variable costs and benefits to the parents. Attempts to understand why and how parental care evolved independently in numerous animal groups often emphasize the role of environmental pressures such as predation, ephemeral resources, and, more generally, the harshness of environment. The fossil record can, in principle, provide minimum age constraints on the evolution of life-history traits, including brood care and key information on the reproductive strategies of extinct organisms. New, exceptionally preserved specimens of the weakly sclerotized arthropod Waptia fieldensis from the middle Cambrian (ca. 508 million years ago) Burgess Shale, Canada, provide the oldest example of in situ eggs with preserved embryos in the fossil record. The relatively small clutch size, up to 24 eggs, and the relatively large diameter of individual eggs, some over 2 mm, contrast with the high number of small eggs—found without preserved embryos—in the bivalved bradoriid arthropod Kunmingella douvillei from the Chengjiang biota (ca. 515 million years ago). The presence of these two different parental strategies suggests a rapid evolution of a variety of modern-type life-history traits, including extended investment in offspring survivorship, soon after the Cambrian emergence of animals. Together with previously described brooded eggs in ostracods from the Upper Ordovician (ca. 450 million years ago), these new findings suggest that the presence of a bivalved carapace played a key role in the early evolution of parental care in arthropods
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