LOGIN

RSS Facebook Twitter YouTube
GLOSSARY       

SEARCHGLOSSARY

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

PROFILESEARCH

Avatar

Please consider registering
guest

sp_LogInOut Log In sp_Registration Register

Register | Lost password?
Advanced Search

— Forum Scope —




— Match —





— Forum Options —





 

Minimum search word length is 4 characters - maximum search word length is 84 characters

sp_Feed Topic RSS sp_TopicIcon
Strong population genetic structuring in an annual fish, Nothobranchius furzeri, suggests multiple savannah refugia in southern Mozambique
September 16, 2013
11:15 am
Avatar
Erich
Member
Forum Posts: 86
Member Since:
September 30, 2012
sp_UserOfflineSmall Offline

 

BMC Evolutionary Biology 2013, 13:196 doi:10.1186/1471-2148-13-196 Published: 12 September 2013

 

Abstract (provisional)

Background

Intraspecific genetic variation of African fauna has been significantly affected by   pronounced climatic fluctuations in Plio-Pleistocene, but, with the exception of large   mammals, very limited empirical data on diversity of natural populations are available   for savanna-dwelling animals. Nothobranchius furzeri is an annual fish from south-eastern   Africa, inhabiting discrete temporary savannah pools outside main river alluvia. Their   dispersal is limited and population processes affecting its genetic structure are   likely a combination of those affecting terrestrial and aquatic taxa. N. furzeri is   a model taxon in ageing research and several populations of known geographical origin   are used in laboratory studies. Here, we analysed the genetic structure, diversity,   historical demography and temporal patterns of divergence in natural populations of   N. furzeri across its entire distribution range.

Results

Genetic structure and historical demography of N. furzeri were analysed using a combination   of mitochondrial (partial cytochrome b sequences, 687 bp) and nuclear (13 microsatellites)   markers in 693 fish from 36 populations. Genetic markers consistently demonstrated   strong population structuring and suggested two main genetic groups associated with   river basins. The split was dated to the Pliocene (>2 Mya). The northern group inhabits   savannah pools across the basin of the intermittent river Chefu in south-western Mozambique   and eastern Zimbabwe. The southern group (from southernmost Mozambique) is subdivided,   with the River Limpopo forming a barrier (maximum divergence time 1 Mya). A strong   habitat fragmentation (isolated temporary pools) is reflected in significant genetic   structuring even between adjacent pools, with a major influence of genetic drift and   significant isolation-by-distance. Analysis of historical demography revealed that   the expansion of both groups is ongoing, supported by frequent founder effects in   marginal parts of the range and evidence of secondary contact between Chefu and Limpopo   populations.

Conclusions

We demonstrated: (1) ancient (pre-Pleistocene) divergence between the two main N.   furzeri lineages, their recent secondary contact and lack of reproductive isolation;   (2) important genetic structuring attributed to the fragmented nature of their environment   and isolation-by-distance, suggesting that dispersal is limited, occurs over short   distances and is not directly associated with river routes; (3) an apparent role of   the River Limpopo as a barrier to dispersal and gene flow.

 

http://www.biomedcentral.com/1.....6/abstract

 

Forum Timezone: Europe/Paris

Most Users Ever Online: 246

Currently Online:
1 Guest(s)

Currently Browsing this Page:
1 Guest(s)

Devices in use: Desktop (1)

Top Posters:

Stefan: 1567

Plaamoo: 1257

mikev: 1134

Malti: 1099

Mark Duffill: 1012

Member Stats:

Guest Posters: 0

Members: 30520

Moderators: 0

Admins: 2

Forum Stats:

Groups: 4

Forums: 10

Topics: 4603

Posts: 36641

Newest Members: datfish, wong123, Kevin20359, troides, noos

Administrators: dunc: 1323, Matt: 8239