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SPECIATION AND MACROEVOLUTION [PDF]

open access: yesEvolution, 1982
Species and higher taxa represent, phenomenologically, two very different levels in the hierarchical organization of the living world. Ever since there has been a concept of evolution, there has been the problem how one can get from the species level to that of the higher categories.
openaire   +2 more sources

Trace metals in the open oceans: speciation modelling based on humic type ligands [PDF]

open access: yes, 2011
The speciation of trace metals in the oceans is typically explained by invoking the concept of metal binding to specific organic ligands, but a lack of detailed knowledge about the ligands has impeded the formulation of comprehensive models to predict ...
Stockdale, Anthony   +7 more
core   +1 more source

Mapping Chemical Elements and Iron Oxidation States in the Substantia Nigra of 6-Hydroxydopamine Lesioned Rats Using Correlative Immunohistochemistry With Proton and Synchrotron Micro-Analysis

open access: yesFrontiers in Neuroscience, 2019
Brain metal homeostasis is altered in neurodegenerative diseases and the concentration, the localization and/or the chemical speciation of the elements can be modified compared to healthy individuals.
Asuncion Carmona   +13 more
doaj   +1 more source

Geographic range size and speciation in honeyeaters

open access: yesBMC Ecology and Evolution, 2022
Background Darwin and others proposed that a species’ geographic range size positively influences speciation likelihood, with the relationship potentially dependent on the mode of speciation and other contributing factors, including geographic setting ...
Eleanor M. Hay   +2 more
doaj   +1 more source

Little ecological divergence associated with speciation in two African rain forest tree genera [PDF]

open access: yes, 2011
Background The tropical rain forests (TRF) of Africa are the second largest block of this biome after the Amazon and exhibit high levels of plant endemism and diversity. Two main hypotheses have been advanced to explain speciation processes that have led
Porter-Morgan, H.   +19 more
core   +2 more sources

Speciation and phylogeography in the cosmopolitan marine moon jelly, Aurelia sp. [PDF]

open access: yes, 2005
Background: The cosmopolitan moon jelly Aurelia is characterized by high degrees of morphological and ecological plasticity, and subsequently by an unclear taxonomic status. The latter has been revised repeatedly over the last century, dividing the genus
Jarms, Gerhard   +3 more
core   +1 more source

Frequency-dependent selection predicts patterns of radiations and biodiversity. [PDF]

open access: yesPLoS Computational Biology, 2010
Most empirical studies support a decline in speciation rates through time, although evidence for constant speciation rates also exists. Declining rates have been explained by invoking pre-existing niches, whereas constant rates have been attributed to ...
Carlos J Melián   +4 more
doaj   +1 more source

Sexual and postmating reproductive isolation between allopatric Drosophila montana populations suggest speciation potential [PDF]

open access: yes, 2011
This work was funded by a European Commission Research Training Grant RTN2-2001-00049, the Centre of Excellence for Evolutionary Research at the University of Jyväskylä and a Marie Curie Initial Training Network, ‘Understanding the evolutionary origin of
Jennings, Jackson H.   +9 more
core   +1 more source

In search of the Goldilocks zone for hybrid speciation II: hard times for hybrid speciation? [PDF]

open access: yes, 2023
Hybridization opens a unique window for observing speciation mechanisms and is a potential engine of speciation. One controversially discussed outcome of hybridization is homoploid hybrid speciation by reciprocal sorting, where a hybrid population ...
Vedanth Sriram   +5 more
core   +1 more source

Genome-wide tests for introgression between cactophilic Drosophila implicate a role of inversions during speciation [PDF]

open access: yes, 2015
K.L. was funded by a junior research fellowship from the National Environmental Research Council, UK (NE/I020288/1, NBAF659).Models of speciation-with-gene-flow have shown that the reduction in recombination between alternative chromosome arrangements ...
Etges, William J   +9 more
core   +1 more source

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