<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Chew, Robert M.</style></author><author><style face="normal" font="default" size="100%">Whitford, W. G.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A long-term positive effect of kangaroo rats (&lt;i&gt;Dipodomys spectabilis&lt;/i&gt;) on creosotebushes (&lt;i&gt;Larrea tridentata&lt;/i&gt;)</style></title></titles><keywords><keyword><style  face="normal" font="default" size="100%">JRN</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1992</style></year></dates><volume><style face="normal" font="default" size="100%">22</style></volume><pages><style face="normal" font="default" size="100%">375-386</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Several studies have shown the effects of the mounds of the banner-tailed kangaroo rat (&lt;i&gt;Dipodomys spectabilis&lt;/i&gt; Merriam) on desert annuals.  There can be effects on density, biomass and composition of the herbaceous assemblage (Moroka et al., 1982; Mun &amp; Whitford, 1989).  As a result of a long-term study of a site in south-eastern Arizona, we observed a positive effect of these mounds on the growth, flowering and fruiting, and survival of creosotebush, which is the dominant woody perennial of the community.  This effect became obvious at this site long after the kangaroo rats disapppeared from the system, probably as a result of invasion of creosotebushes and other shrubby vegetaion into what was previously a desert grassland system.  Whereas creosotebushes had a negative effect on the kangaroo rat population, the mounds created by these rodents have had a residual positive effect on the creosotebushes. A number of measurements were made to examine the nature of this unusual, if not unique, relationship, and to provide some basis for speculation as to the cause(s) of the positive effect.</style></abstract><accession-num><style face="normal" font="default" size="100%">LTER.1992-91588</style></accession-num></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Chew, Alice Eastlake</style></author><author><style face="normal" font="default" size="100%">Chew, Robert M.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Body size as a determinant of small-scale distributions of ants in evergreen woodland southeastern Arizona</style></title></titles><keywords><keyword><style  face="normal" font="default" size="100%">JRN</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1980</style></year></dates><volume><style face="normal" font="default" size="100%">27</style></volume><pages><style face="normal" font="default" size="100%">189-202</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Distributions and abundances of ants were determined on the N, E, W and S upper slopes of a conical hill that had a gradient of conditons from moist-cool oak-juniper-pine woodland to warm-dry open shrub woodland.  Species distributions varied remakably with slope, even in terms of subfamilies and unique common species.  A formicine was the most abundant species on the north slope.  A different species of dolichoderine was most abundant on the other slopes.  The assemblages of ant species were much more distinct for these small sites on each slope than are the known groups of species associated with vegetation types on a broad geographical basis.  Interpretation of the causes of such specific assemblages awaits detailed information on species ecologies.  However, there is considerable circumstantial evidence that body size of pairs of species in the same site was least for common species of the same feeding quild; similarity was greater when one or both members of a pair were uncommon; similarites were highesst for species on different guilds.  Combinations of species that would have had very high size overlaps did not occur together.  Some combinations that occurred were those that had the least overlap possible for the species known to occur on the entire hill.</style></abstract><accession-num><style face="normal" font="default" size="100%">LTER.1980-92134</style></accession-num></record></records></xml>