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1.
Gigascience ; 3(1): 2, 2014 Mar 07.
Article in English | MEDLINE | ID: mdl-24606731

ABSTRACT

The co-authors of this paper hereby state their intention to work together to launch the Genomic Observatories Network (GOs Network) for which this document will serve as its Founding Charter. We define a Genomic Observatory as an ecosystem and/or site subject to long-term scientific research, including (but not limited to) the sustained study of genomic biodiversity from single-celled microbes to multicellular organisms.An international group of 64 scientists first published the call for a global network of Genomic Observatories in January 2012. The vision for such a network was expanded in a subsequent paper and developed over a series of meetings in Bremen (Germany), Shenzhen (China), Moorea (French Polynesia), Oxford (UK), Pacific Grove (California, USA), Washington (DC, USA), and London (UK). While this community-building process continues, here we express our mutual intent to establish the GOs Network formally, and to describe our shared vision for its future. The views expressed here are ours alone as individual scientists, and do not necessarily represent those of the institutions with which we are affiliated.

2.
PLoS One ; 7(5): e37528, 2012.
Article in English | MEDLINE | ID: mdl-22666362

ABSTRACT

Although 21(st) century ecology uses unprecedented technology at the largest spatio-temporal scales in history, the data remain reliant on sound taxonomic practices that derive from 18(th) century science. The importance of accurate species identifications has been assessed repeatedly and in instances where inappropriate assignments have been made there have been costly consequences. The National Ecological Observatory Network (NEON) will use a standardized system based upon an integrative taxonomic foundation to conduct observations of the focal terrestrial insect taxa, ground beetles and mosquitoes, at the continental scale for a 30 year monitoring program. The use of molecular data for continental-scale, multi-decadal research conducted by a geographically widely distributed set of researchers has not been evaluated until this point. The current paper addresses the development of a reference library for verifying species identifications at NEON and the key ways in which this resource will enhance a variety of user communities.


Subject(s)
Classification/methods , Coleoptera/classification , Animals , Female , Male , Societies , United States
3.
Ann Bot ; 101(1): 145-52, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17993653

ABSTRACT

BACKGROUND AND AIMS: Polyploidy is a central force structuring genetic diversity in angiosperms, but its ecological significance and modes of origin are not fully understood. This work investigated the patterns of coexistence and molecular relatedness of polyploids in the perennial herb, Arnica cordifolia. METHODS: The local- and broad-scale distributions of cytotypes were analysed using flow cytometry. Samples were collected from both roadside and understorey habitats to test the hypothesis of niche separation between triploids and tetraploids. The nuclear rDNA internal transcribed spacer (ITS) and plastid rpl16 spacer, trnL intron plus trnL-trnF spacer and trnK 3' intron regions were sequenced. KEY RESULTS: Broad-scale sampling established that both triploids and tetraploids were common throughout the range of the species, pentaploids were rare, and diploids were not found. Local-scale sampling revealed coexistence of both triploids and tetraploids within the majority of sites. Triploids and tetraploids were equally represented in the understorey and roadside habitat. Triploids were more variable than tetraploids, but both cytotypes shared polymorphisms in ITS. CONCLUSIONS: Coexistence of cytotypes appears to be the norm in A. cordifolia, but habitat differentiation (roadside vs. understorey) is not supported as a coexistence mechanism. Molecular analyses supported multiple events creating triploids but revealed a lack of variation in the tetraploids. Additionally, sequence polymorphisms in ITS suggested a hybridization event prior to polyploidization.


Subject(s)
Arnica/genetics , Polyploidy , Arnica/classification , Colorado , DNA, Chloroplast/chemistry , DNA, Intergenic/chemistry , Ecosystem , Haplotypes , Hybridization, Genetic , Pacific States , Polymorphism, Genetic , Sequence Analysis, DNA
4.
New Phytol ; 175(4): 764-772, 2007.
Article in English | MEDLINE | ID: mdl-17688591

ABSTRACT

Reproductive isolation via apomixis is one way for newly created cytotypes to persist and coexist with other cytotypes. Arnica cordifolia (Asteraceae) has both triploid and tetraploid cytotypes co-occurring in many locations. The rate of apomixis in each cytotype was explored as a mechanism for the maintenance of sympatric cytotypes. Flow cytometry was used on both adults and seeds from mixed cytotype populations to estimate reproductive mode and to evaluate the relationship between cytotype frequency and reproductive success. Flowering time was surveyed to look for temporal reproductive isolation between cytotypes. Both triploids and tetraploids can be asexual. Apomixis in A. cordifolia is usually autonomous, not pseudogamous as previously thought. Sexual reproduction appears to be uncommon. The minority cytotype in each population does not produce fewer seeds, confirming that minority cytotype exclusion is unlikely to occur via reproductive disadvantage. Triploids flowered earlier than tetraploids, but with much overlap. Asexual reproduction is an important factor promoting the coexistence of cytotypes in this system. Other mechanisms maintaining populations of sympatric cytotypes are not well studied or understood and warrant further investigation.


Subject(s)
Arnica/cytology , Arnica/physiology , Reproduction, Asexual , Arnica/genetics , Ecosystem , Flowers , Ploidies , Seeds
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