نتایج جستجو برای: faunal ramain

تعداد نتایج: 2634  

2007
Sean R. Connolly Arnold I. Miller

-During the Ordovician Radiation, domination of benthic marine communities shifted away from trilobites, toward articulate brachiopods, and, to a lesser degree, toward bivalves and gastropods. In this paper, we identify the patterns in origination and extinction probabilities that gave rise to these transitions. Using methods adapted from capture-mark-recapture (CMR) population studies, we esti...

2016
Jonathan S Lefcheck Scott R Marion Alfonso V Lombana Robert J Orth

Human-driven habitat fragmentation is cited as one of the most pressing threats facing many coastal ecosystems today. Many experiments have explored the consequences of fragmentation on fauna in one foundational habitat, seagrass beds, but have either surveyed along a gradient of existing patchiness, used artificial materials to mimic a natural bed, or sampled over short timescales. Here, we de...

2003
R. Lee Lyman R. Jay Lyman

Paleozoologists and taphonomists have long recognized various properties of quantification and sampling with respect to collections they study. Those same properties attend samples of modern owl pellets. The particular skeletal elements identified and the way in which prey remains are grouped for tallying both influence measures of relative prey abundance in a collection of 56 barn-owl (Tyto al...

2011
J. Travis Smith Jeremy B.C. Jackson

—The marine faunas of tropical America underwent substantial evolutionary turnover in the past 3 to 4 million years in response to changing environmental conditions associated with the rise of the Isthmus of Panama, but the ecological signature of changes within major clades is still poorly understood. Here we analyze the paleoecology of faunal turnover within the family Pectinidae (scallops) o...

2006
D. Ross Robertson Frances Karg Rodrigo Leao de Moura Benjamin C. Victor Giacomo Bernardi

Relationships based on mtDNA and nDNA sequences were used to assess eVects of two major geographic barriers (the >30 myo Atlantic ocean and the »11 myo Amazon–Orinoco outXow) on speciation among Atlantic parrotWshes (Sparisoma and Nicholsina). Allopatric distributions of sister taxa implicate isolating actions of both barriers in all recent speciation in these Wshes, with no clear indications t...

2007
Marie A. Simovich

The faunal community of California’s vernal pools is less obvious and has been less studied than the floral community but is similarly diverse, endemic, and endangered. Species richness and composition vary between pool types, between pools of a given type, and within individual pools between years and through the season. The physiology, life history, and ecology of the pool organisms contribut...

2017
James A. Sanchez Delbert L. Smee Meredith Diskin Carl Trettin

Climate change is altering the distribution of foundation species, with potential effects on organisms that inhabit these environments and changes to valuable ecosystem functions. In the Gulf of Mexico, black mangroves (Avicennia germinans) are expanding northward into salt marshes dominated by Spartina alterniflora (hereafter Spartina). Salt marshes are essential habitats for many organisms, i...

Journal: :caspian journal of enviromental sciences 0

this paper provides information on the geographic distributions of two cyprinid species: hemiculter leucisculus (basilewsky, 1855) and alburnus caeruleus heckel, 1843, in the world and the entire drainage systems in iran. the new distribution records were taken from maroon river (jarrahi river system) and chardaval river (karkheh river system), both in tigris river basin showing wide and narrow...

Journal: :Proceedings of the American Academy of Arts and Sciences 1891

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