<div dir="ltr"><br><div class="gmail_extra"><br><div class="gmail_quote">On Fri, Oct 9, 2015 at 12:00 PM, John Clark <span dir="ltr"><<a href="mailto:johnkclark@gmail.com" target="_blank">johnkclark@gmail.com</a>></span> wrote:</div><div class="gmail_quote"><br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div class="gmail_extra"><div class="gmail_quote"><div><div><font size="4"><font face="arial, helvetica, sans-serif">It's very difficult to say for certain what caused a extinction or what caused </font>semi-cyclic population levels for that matter, and if it happened long ago it's probably impossible. However if the only use of a attribute is decoration to attract a female and if that attribute is clearly detrimental in all other activities, as is the case of the Irish Elk's antlers or the Peacock's tail, then it's not unreasonable to conclude that attribute would reduce the number of individuals in a species compared to what they would have been if the female had used a better rule of thumb to ascertain the fitness of a male. And perhaps it could </font><span style="font-size:large">reduce those population numbers all the way down to zero. </span></div></div></div></div></div></blockquote><div><br></div><div>### It is generally not reasonable to conclude anything in population genetics without doing some math, followed by simulations exploring various assumptions, followed by real-life measurements putting limits on assumptions.</div><div><br></div><div>The least you can do before concluding anything is to read the relevant literature.</div><div><br></div><div>-------------</div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div class="gmail_extra"><div class="gmail_quote"><div><span class=""><div><br></div></span><div><div><font size="4"><font face="arial, helvetica, sans-serif">Not necessarily. Females could become so rare that the poor male with small antlers can't find any females at all, much less females that will mate with him.</font></font></div></div></div></div></div></div></blockquote><div><br></div><div>### You are concluding that the cost of a signal presented by some males could somehow reduce the survival of females.</div><div><br></div><div>So tell me, how can an extra-large large peacock's tail, found in e.g. 10% of males, reduce the numbers of peahens down to zero ("any females at all")?</div><div> </div><div>---------------</div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div class="gmail_extra"><div class="gmail_quote"><div><br></div><div><div><font size="4"><font face="arial, helvetica, sans-serif"></font>Not necessarily. There might not be any real competitors as the big antler males are all dead but the female would not know that, there would still be competitors in her mind so she might refuse to settle for the geek with the ugly small antlers regardless of how practical they were. She wants bling not practicality.</font></div></div></div></div></div></blockquote><div><br></div><div>### This is silly.</div><div><br></div><div> ----------------</div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div class="gmail_extra"><div class="gmail_quote"><span class=""><div><br></div></span><div><div style="font-family:arial,helvetica,sans-serif;display:inline"><font size="4">Not necessarily, not if a female Irish Elk </font></div><font size="4"><div style="font-family:arial,helvetica,sans-serif;display:inline">thought that a male Irish Elk that had antlers of a size that was less than gargantuan to be so repellent that virginity is preferred. And after all for all the female knows there could be a beautiful male out there somewhere with huge grotesquely impractical antlers. </div></font></div></div></div></div></blockquote><div><br></div><div>### Now, since you seem claim expertise in female elk sexuality, tell me how many elks did you see that actively rebuff males in order to protect their virginity?</div><div><br></div><div>Rafał</div></div>
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