Previous estimates of the global generic diversity loss for echinoids at the Cretaceous/Tertiary boundary have been as high as 65%. However, these estimates are based on compilations of occurrence data from the existing literature and are plagued by problems of inconsistent taxonomic usage. Analysis of a taxonomically standardized, phylogenetically framed data set demonstrates that the generic extinction rate for heart urchins was 33%, and that the two constituent orders suffered markedly different fates. Whereas holasteroids lost 56% of their generic diversity at the end of the Cretaceous, only 17% of spatangoid genera became extinct. Correlation of extinction with a range of geographical, environmental, and biological factors has been explored. Survivorship is significantly correlated only with feeding strategy, implying that the extinctions of atelostomate echinoids at the Cretaceous/Tertiary boundary were nutrient driven. In addition, feeding strategy is correlated with atelostomate clade affinity, explaining the differential fates of holasteroids and spatangoids at the end of the Cretaceous.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 27 • No. 1