作者: Diego Balseiro , Beatriz G. Waisfeld
DOI: 10.1016/J.PALAEO.2012.11.019
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摘要: Abstract Although ecological stability has been widely studied in the fossil record, it seldom analyzed trilobite dominated communities. We test these communities from Upper Cambrian–Lower Ordovician of Cordillera Oriental, Northwestern Argentina. The interval spans approximately 5 ma. and for this analysis was divided four smaller scale informal intervals 1.5 to 2 ma. Sampling covers a wide geographic area ~ 7000 km 2 each time bin. In order analyze stability, we tested patterns predicted hypothesis coordinated stasis habitat tracking. For taxonomic turnover. Migrations evolutionary turnovers based on regional global occurrence taxa were assessed. Results indicate important rates immigration emigration, highlighting relevance migration assembly meta-community. percentage carryovers holdovers variable between did not show bimodal pattern, contradicting model. addition, an ordination performed with correspondence suggests that idiosyncratic genus composition. model tracking, biotic gradients environmental fidelity stenotopic conducted. carried out Mantel recurrence present different intervals. results showed are grouped differently every interval, indicating instability gradients. also gradient compared other using Procrustes analysis. respond individualistically changes. Moreover, high errors rare taxa. Because rarity is largely related niche breadth, result many had little fidelity. Overall, study appears be great importance composition local communities, formed distinct structure. Such compositional do convincing evidence support stasis. Finally, concept individualistic tracking more clearly understood light metacommunity processes such as dispersal preferences, rather than process by itself.