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<DIV id=slugline jQuery1347587426013="3"><CITE><ABBR class=slug-jnl-abbrev
title=Science>Science</ABBR><SPAN class=slug-pub-date itemprop="datePublished">
14 September 2012: </SPAN><BR><SPAN class=slug-vol>Vol. 337 </SPAN><SPAN
class=slug-issue>no. 6100 </SPAN><SPAN class=slug-pages>p. 1313 </SPAN><BR>DOI:
<SPAN class=slug-doi title=10.1126/science.1224198>10.1126/science.1224198
</SPAN></CITE></DIV>
<DIV> </DIV>
<DIV class="article abstract-view" jQuery1347587426013="5"
itemprop="articleBody" sizset="0" sizcache="1"><SPAN
class=highwire-journal-article-marker-start></SPAN> </DIV>
<DIV id=article-title-1 itemprop="headline"><FONT size=4>Adaptive Prolonged
Postreproductive Life Span in Killer Whales</FONT></DIV>
<DIV class="article abstract-view" jQuery1347587426013="5"
itemprop="articleBody" sizset="0" sizcache="1">
<DIV id=contrib-1 class=contributor itemscope="itemscope"
itemtype="http://schema.org/Person" itemprop="author" sizset="0"
sizcache="0"><SPAN class=name itemprop="name"><A class=name-search
href="http://www.sciencemag.org/search?author1=Emma+A.+Foster&sortspec=date&submit=Submit">Emma
A. Foster</A></SPAN><A id=xref-aff-1-1 class=xref-aff
href="http://www.sciencemag.org/content/337/6100/1313.short#aff-1"
jQuery1347587426013="21"><SUP>1</SUP></A><SPAN class=xref-sep>,</SPAN><A
id=xref-aff-2-1 class=xref-aff
href="http://www.sciencemag.org/content/337/6100/1313.short#aff-2"
jQuery1347587426013="22"><SUP>2</SUP></A>, <SPAN class=name itemprop="name"><A
class=name-search
href="http://www.sciencemag.org/search?author1=Daniel+W.+Franks&sortspec=date&submit=Submit">Daniel
W. Franks</A></SPAN><A id=xref-aff-3-1 class=xref-aff
href="http://www.sciencemag.org/content/337/6100/1313.short#aff-3"
jQuery1347587426013="23"><SUP>3</SUP></A>, <SPAN class=name itemprop="name"><A
class=name-search
href="http://www.sciencemag.org/search?author1=Sonia+Mazzi&sortspec=date&submit=Submit">Sonia
Mazzi</A></SPAN><A id=xref-aff-4-1 class=xref-aff
href="http://www.sciencemag.org/content/337/6100/1313.short#aff-4"
jQuery1347587426013="24"><SUP>4</SUP></A>, <SPAN class=name itemprop="name"><A
class=name-search
href="http://www.sciencemag.org/search?author1=Safi+K.+Darden&sortspec=date&submit=Submit">Safi
K. Darden</A></SPAN><A id=xref-aff-1-2 class=xref-aff
href="http://www.sciencemag.org/content/337/6100/1313.short#aff-1"
jQuery1347587426013="25"><SUP>1</SUP></A>, <SPAN class=name itemprop="name"><A
class=name-search
href="http://www.sciencemag.org/search?author1=Ken+C.+Balcomb&sortspec=date&submit=Submit">Ken
C. Balcomb</A></SPAN><A id=xref-aff-2-2 class=xref-aff
href="http://www.sciencemag.org/content/337/6100/1313.short#aff-2"
jQuery1347587426013="26"><SUP>2</SUP></A>, <SPAN class=name itemprop="name"><A
class=name-search
href="http://www.sciencemag.org/search?author1=John+K.+B.+Ford&sortspec=date&submit=Submit">John
K. B. Ford</A></SPAN><A id=xref-aff-5-1 class=xref-aff
href="http://www.sciencemag.org/content/337/6100/1313.short#aff-5"
jQuery1347587426013="27"><SUP>5</SUP></A>, <SPAN class=name><A class=name-search
href="http://www.sciencemag.org/search?author1=Darren+P.+Croft&sortspec=date&submit=Submit">Darren
P. Croft</A></SPAN><A id=xref-aff-1-3 class=xref-aff
href="http://www.sciencemag.org/content/337/6100/1313.short#aff-1"
jQuery1347587426013="28"><SUP>1</SUP></A><SPAN class=xref-sep>,</SPAN><A
id=xref-corresp-1-1 class=xref-corresp
href="http://www.sciencemag.org/content/337/6100/1313.short#corresp-1">*</A></DIV>
<P class=affiliation-list-reveal><SUP>1</SUP>Centre for Research in Animal
Behaviour, College of Life and Environmental Sciences, University of Exeter,
Exeter EX4 4QG, UK. <SUP>2</SUP>Center for Whale Research, 355 Smugglers Cove
Road, Friday Harbor, WA 98250, USA. <SUP>3</SUP>Department of Biology,
University of York, York YO10 5DD, UK. <SUP>4</SUP>Department of Mathematics,
University of York, York YO10 5DD, UK. <SUP>5</SUP>Pacific Biological Station,
Fisheries and Oceans Canada, Nanaimo, BC V9T 6N7, Canada. E-mail: <A
href="mailto:d.p.croft@exeter.ac.uk">d.p.croft@exeter.ac.uk</A></P>
<DIV id=abstract-2 class="section abstract">
<H2><FONT size=2>Abstract</FONT></H2>
<P id=p-2>Prolonged life after reproduction is difficult to explain
evolutionarily unless it arises as a physiological side effect of increased
longevity or it benefits related individuals (i.e., increases inclusive
fitness). There is little evidence that postreproductive life spans are adaptive
in nonhuman animals. By using multigenerational records for two killer whale
(<EM>Orcinus orca</EM>) populations in which females can live for decades after
their final parturition, we show that postreproductive mothers increase the
survival of offspring, particularly their older male offspring. This finding may
explain why female killer whales have evolved the longest postreproductive life
span of all nonhuman animals. </P></DIV></DIV></FONT></BODY></HTML>