[MARMAM] Abstract: Can Genetic Differences Explain Vocal Dialect Variation in Sperm Whales
ler4 at st-andrews.ac.uk
Wed Nov 23 08:50:36 PST 2011
The paper below appeared online recently. For those with journal access, it can be found at: http://www.springerlink.com/content/25v60uu35j5369r1/
Otherwise I can send you a pdf if you email me (ler4 at st-andrews.ac.uk).
Can Genetic Differences Explain Vocal Dialect Variation in Sperm Whales, Physetermacrocephalus?
Luke Rendell, Sarah L. Mesnick, Merel L. Dalebout, Jessica Burtenshaw and Hal Whitehead
Sperm whale social groups can be assigned to vocal clans based on their production of codas, short stereotyped patterns of clicks. It is currently unclear whether genetic variation could account for these behavioural differences. We studied mitochondrial DNA (mtDNA) variation among sympatric vocal clans in the Pacific Ocean, using sequences extracted from sloughed skin samples. We sampled 194 individuals from 30 social groups belonging to one of three vocal clans. As in previous studies of sperm whales, mtDNA control region diversity was low (π = 0.003), with just 14 haplotypes present in our sample. Both hierarchical AMOVAs and partial Mantel tests showed that vocal clan was a more important factor in matrilineal population genetic structure than geography, even though our sampling spanned thousands of kilometres. The variance component attributed to vocal dialects (7.7%) was an order of magnitude higher than those previously reported in birds, while the variance component attributed to geographic area was negligible. Despite this, the two most common haplotypes were present in significant quantities in each clan, meaning that variation in the control region cannot account for behavioural variation between clans, and instead parallels the situation in humans where parent-offspring transmission of language variation has resulted in correlations with neutral genes. Our results also raise questions for the management of sperm whale populations, which has traditionally been based on dividing populations into geographic ‘stocks’, suggesting that culturally-defined vocal clans may be more appropriate management units.
Keywords Sperm whale – Vocal dialect – Cultural transmission – Genetic population structure
Dr. Luke Rendell
Post-Doctoral Research Fellow
Tel: (44)(0)1334 463499
E-mail: ler4 at st-andrews.ac.uk
School of Biology, University of St. Andrews
Bute Medical Building, Westburn Lane,
St. Andrews, Fife
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