A TEST OF BIOGEOGRAPHICAL, ENVIRONMENTAL, AND ECOLOGICAL EFFECT ON MIDDLE AND LATE TRIASSIC BRACHIOPOD AND BIVALVE ABUNDANCE PATTERNS

摘要: Analysis of Middle Triassic data indicates that biogeography influences sample distributions, whereas depositional environment and stratigraphic position play secondary roles in governing patterns. During this time, taxa differed among biogeographic realms, while the general ecology remained same: epifaunal benthos— pedunculate epibyssate suspension feeders—dominate samples much as they did Early Triassic. In contrast, Late prove to be more complex terms compared Here, guild structure dictates faunal patterns addition realm position, an overall increase infaunal life habits occurs—burrowing deposit feeders increase. Although diversity after mass extinction began recover at Early-Middle boundary, our results indicate stable through until modern (e.g., infaunalization) increased We conclude taxonomic ecological differences geographic regions recorded initiation a mobile habit indicative lifestyle. Our also modernization not necessarily unfold simultaneously coordinated fashion within throughout time. Instead, details expansion or stability may region specific.