02513nas a2200277   4500008004100000245013100041210006900172260000900241300001400250490000700264520161000271653001501881653002801896653000901924653002601933653002501959653001701984653001402001100002802015700002302043700002702066700002302093700002202116700002502138856007202163       2001                        eng d00aPhylogenetic analysis of partial sequences of Elongation Factor 1alpha identifies major groups of lice (Insecta: Phthiraptera)0 aPhylogenetic analysis of partial sequences of Elongation Factor   c2001  a202 - 2150 v193 a<p>As a first attempt to use molecular data to resolve the relationships between the four suborders of lice and within the suborder Ischnocera, we sequenced a 347-bp fragment of the elongation factor 1 gene of 127 lice (Insecta: Phthiraptera) as well as outgroup taxa from the order Psocoptera. A number of well-supported monophyletic groups were found but the relationships among many of these groups could not be resolved. While it is probable that multiple substitutions at high divergences and ancient radiation over a short period of time have contributed to the problem, we attribute most of this lack of resolution to the high ratio of taxa to characters. Nevertheless, the sequence data unequivocally support a number of important relationships that are at variance with the conclusions of morphological taxonomy. These include the sister group relationship of Chelopistes and Oxylipeurus, two lice occupying different ecological niches on the same host, which have previously been assigned to different families. These results provide evidence in support of the hypothesis that lice have speciated in situ on the host in response to niche specialization and that this has given rise to convergent morphologies in the lice of different host groups which share similar ecological niches. We discuss our attempts to overcome the limitations of this large data set, including the use of leaf stability analysis, a new method for analyzing the stability of taxa in a phylogenetic tree, and examine a number of hypotheses of relationships based on both traditional taxonomy and host associations.</p>
10aIschnocera10aleaf stability analysis10alice10amolecular systematics10aniche specialization10aPhthiraptera10aPhylogeny1 aCruickshank, Robert, H.1 aJohnson, Kevin, P.1 aSmith, Vincent, Stuart1 aAdams, Richard, J.1 aClayton, Dale, H.1 aPage, Roderic, D. M.  uhttp://www.phthiraptera.info/sites/phthiraptera.info/files/1204.pdf