26 research outputs found
Ants Sow the Seeds of Global Diversification in Flowering Plants
Background: The extraordinary diversification of angiosperm plants in the Cretaceous and Tertiary periods has produced an
estimated 250,000–300,000 living angiosperm species and has fundamentally altered terrestrial ecosystems. Interactions
with animals as pollinators or seed dispersers have long been suspected as drivers of angiosperm diversification, yet
empirical examples remain sparse or inconclusive. Seed dispersal by ants (myrmecochory) may drive diversification as it can reduce extinction by providing selective advantages to plants and can increase speciation by enhancing geographical
isolation by extremely limited dispersal distances.
Methodology/Principal Findings: Using the most comprehensive sister-group comparison to date, we tested the hypothesis that myrmecochory leads to higher diversification rates in angiosperm plants. As predicted, diversification rates
were substantially higher in ant-dispersed plants than in their non-myrmecochorous relatives. Data from 101 angiosperm
lineages in 241 genera from all continents except Antarctica revealed that ant-dispersed lineages contained on average
more than twice as many species as did their non-myrmecochorous sister groups. Contrasts in species diversity between
sister groups demonstrated that diversification rates did not depend on seed dispersal mode in the sister group and were
higher in myrmecochorous lineages in most biogeographic regions.
Conclusions/Significance: Myrmecochory, which has evolved independently at least 100 times in angiosperms and is
estimated to be present in at least 77 families and 11 000 species, is a key evolutionary innovation and a globally important driver of plant diversity. Myrmecochory provides the best example to date for a consistent effect of any mutualism on largescale diversification
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Serum Erythropoietin and Hemoglobin Affinity for Oxygen in Patients Phlebotomized for Polycythemia Vera
Resection of Pancreatic Metastasis from Renal Cell Carcinoma and an Early Gastric Cancer
Immunohistochemical analysis on normal nephrogenesis and Wilms' tumour using monoclonal antibodies reactive with lymphohaemopoietic antigens
Molecular genetics of Wilms' tumour
Journal of Paediatrics and Child Health315379-383JPCH