San Marco and evolutionary biology

Gould and Lewontin use San Marco, Venice, to criticise the adaptationist program in biology. Following their lead, the architectural term “spandrel” is now widely used in biology to denote a feature that is a necessary byproduct of other aspects of the organism. I review the debate over San Marco and argue that the spandrels are not necessary in the sense originally used by Gould and Lewontin. I conclude that almost all the claims that Gould makes about San Marco are wrong and that it is reasonable to view the architectural spandrel as an adaptation. The spandrels example has not provided a good illustration of why adaptive explanations should be avoided. In fact, it can be used as an example of how adaptive explanations can be dismissed even when there is evidence in their favour. I also discuss the use of the concept of a spandrel in biology.     

Association patterns of bottlenose dolphins (Tursiops truncatus) in Bahía San Antonio,Argentina

This study aims to investigate the association patterns of a small and resident population of bottlenose dolphins (Tursiops truncatus) in Bahía San Antonio (Argentina), and assess any seasonal variation in view of the reported seasonal variation in the population's grouping behavior. The estimation of social differentiation (S) was 0.29 (SE = 0.08), suggesting a homogenous society. The half‐weight index (HWI) averaged 0.23 (± 0.06), with evidence of long‐term preferred associations. However, data showed seasonal variation in the association patterns. In winter, when large groups were reported in this population, HWI values averaged 0.30 (± 0.09) with no indication of preferred or avoided associations. However, during summer, when group size was generally small, HWI values averaged 0.14 (± 0.07), with an indication of preferred/avoided associations. This study indicates that the social structure of the bottlenose dolphins in Bahía San Antonio seems relatively homogenous and flexible over time, with the formation of a random social network at times when large aggregations are formed, and a more disconnected network made up of strongly connected components when the cost of grouping is high.     

Insulin Sensitivity,Body Fat Distribution,and Family Diabetes History: The IRAS Family Study

Objectives : Markers of insulin resistance are often apparent in nondiabetic relatives of subjects with type 2 diabetes. Whether diabetes family history (FH) also predicts visceral fat accumulation and, if so, whether the increased insulin resistance in relatives of diabetic subjects occurs independently of visceral fat accumulation are not known. Research Methods and Procedures : To examine this issue, we studied the relationship of diabetes FH with insulin sensitivity and fat measures, measured by minimal model analysis and computed tomography, respectively, in families participating in the Insulin Resistance Atherosclerosis (IRAS) Family Study. FH scores were based on the diabetes status of the participants’ parents and older siblings. Results : FH scores were significantly correlated with reduced insulin sensitivity (p < 0.05) and increased subcutaneous (p < 0.05) and visceral (p < 0.05, San Antonio only) fat in families from San Antonio and Los Angeles but not in the leaner Hispanic families from San Luis Valley. There was no evidence for a stronger association of FH score with visceral fat accumulation than with subcutaneous fat or insulin resistance. Discussion : The absence of an association between FH score and insulin resistance/fat accumulation in San Luis Valley is consistent with the idea that the expression of transmitted diabetes genes may be suppressed in leaner, more physically active populations.     

Invasion by a Japanese marine microorganism in western North America

The earliest record in western North America of Trochammina hadai Uchio, a benthic foraminifer common in Japanese estuaries, is from sediment collected in Puget Sound in 1971. It was first found in San Francisco Bay in sediment samples taken in 1983, and since 1986 has been collected at 91% of the sampled sites in the Bay, constituting up to 93% of the foraminiferal assemblage at individual sites. The species is also present in recent sediment samples from 12 other sites along the west coast of North America. The evidence indicates that T. hadai is a recent introduction to San Francisco Bay, and is probably also not native to the other North American sites. Trochammina hadai was probably transported from Japan in ships' ballast tanks, in mud associated with anchors, or in sediments associated with oysters imported for mariculture. Its remarkable invasion of San Francisco Bay suggests the potential for massive, rapid invasions by other marine microorganisms.     

Population structure of mud flounder Paralichthys orbignyanus from the south-western Atlantic Ocean

The mud flounder Paralichthys orbignyanus (Pleuronectiformes, Paralichthyidae) inhabits shallow waters of low salinities and mud bottoms in the temperate marine coastal regions of the Bonaerensean Ecoregion of the Argentinean Biogeographic Province in the south-western Atlantic Ocean. Specimens of P. orbignyanus were collected from Lagoa dos Patos (LDP) (southern Brazil), Mar Chiquita (MCH) and Marisol (MAR) both located in Buenos Aires (Argentina), and San Antonio Oeste (SAO) in the San Matías Gulf, Rio Negro (Argentina). A fragment of the mitochondrial DNA of the Control Region and seven microsatellite loci were characterized. In the Control Region, P. orbignyanus showed high variability, low nucleotide diversity, mild population expansion and a coalescence time of 35,000 years before the present. Flounders provided evidence of a genetic structure between the sampling sites LDP, MCH, MAR vs. SAO. On the other hand, P. orbignyanus displayed a lower to moderate contemporary genetic structure among all samples except between LDP and MCH. With no evidence of isolation by distance, this analysis supports a model of limited gene flow that is likely to be associated with a consistent larvae retention in all sampling sites. In addition, the present connectivity is ascribed to a lower migration process from SAO in the San Matías Gulf congruent with the prevailing littoral drift.     

Exotic plant invasions in an endemic‐rich habitat: The spread of an introduced Australian grass,Agrostis avenacea J. F. Gmel., in California vernal pools

Abstract The present abundance and historical spread of an exotic grass, Agrostis avenacea, is documented for California, USA, and for the vernal pools of San Diego County in particular. Agrostis avenacea is native to Australia where it is a common grass of ephemeral and fluctuating wetlands. California vernal pools, by reason of their extreme variability and high endemism, have been thought to be relatively resistant to invasion. The recent expansion of A. avenacea in San Diego County demonstrates, however, that the alleged resistance is probably a function of a relatively small pool of invaders and a low probability of targeted dispersal. Although A. avenacea is now abundant in pools with little current disturbance, human disturbance appears to have been a major factor that facilitated its initial establishment. This specific instance adds to the mounting evidence that there are probably few, if any, habitats immune to invasion.     

Rickettsia felis in cat fleas,Ctenocephalides felis parasitizing opossums,San Bernardino County,California

Los Angeles and Orange Counties are known endemic areas for murine typhus in California; however, no recent reports of flea‐borne rickettsioses are known from adjacent San Bernardino County. Sixty‐five opossums (Didelphis virginiana) were trapped in the suburban residential and industrial zones of the southwestern part of San Bernardino County in 2007. Sixty out of 65 opossums were infested with fleas, primarily cat fleas, Ctenocephalides felis (Bouché, 1835). The flea minimum infection rate with Rickettsia felis was 13.3% in pooled samples and the prevalence was 23.7% in single fleas, with two gltA genotypes detected. In spite of historic records of murine typhus in this area, no evidence for circulation of R. typhi in fleas was found during the present study. Factors contributing to the absence of R. typhi in these cat fleas in contrast to its presence in cat fleas from Orange and Los Angeles Counties are unknown and need to be investigated further in San Bernardino County.     

Management of natural <Emphasis Type="Italic">Ulva</Emphasis> spp. blooms in San Quintin Bay,Baja California: Is it justified?

According to Zertuche-González et al. (2009), Ulva spp. blooms, favored by oyster cultivation, are likely displacing subtidal meadows of Zostera marina in San Quintin Bay, Baja California. The authors propose a partial removal of the seaweed to reduce the risk of eutrophication and eelgrass displacement in the bay. We warn about the removal of Ulva spp. biomass by raising six arguments that emphasize the necessity of a historical and ecosystem-based management for San Quintin Bay. First, processes other than competitive exclusion by Ulva spp. blooms more likely explain changes of Z. marina subtidal meadows in the past decade. Second, there is no consistent evidence that oyster cultivation is promoting blooms of Ulva spp. and the loss of eelgrass. Third, the removal of Ulva spp. biomass is based on experiences of heavily anthropogenically eutrophic systems, while San Quintin Bay is not. Fourth, the proposed course of actions to restore eelgrass meadows ignores general historical baselines of estuarine and coastal systems by confusing what it means to be “pristine.” Fifth, despite the important experimental evidence indicating strong top–down control in temperate seagrass meadows, Zertuche-González et al. (2009) underestimated the capacity of consumers in structuring dynamics of vegetated soft-bottom communities in San Quintin Bay. Sixth, Ulva expansa may exert positive effects on seagrass ecosystem properties and functions. Instead, we propose protection against the propagation of unsustainable practices in the bay, and the reintroduction of large consumers that are now absent in this ecosystem. An ecosystem-based analysis of the role of Ulva spp. on eelgrass dynamics is needed.     

Central Adiposity Determines Prevalence Differences of the Metabolic Syndrome

Objective: To compare the expression of the metabolic syndrome in Spain and San Antonio, TX, two populations with major differences regarding their cardiovascular risk profile. Research Methods and Procedures: Cross‐sectional analysis of population‐based, epidemiological surveys using the metabolic syndrome definition of the National Cholesterol Education Program. In San Antonio, we limited our analysis to non‐Hispanic whites because non‐Hispanic whites are largely of European ancestry (n = 1339 in San Antonio and 2947 in Spain) Results: In men, increased central adiposity was more prevalent in San Antonio than in Spain (29.7 vs. 23.0%, p < 0.0001); in women, it was less prevalent in San Antonio than in Spain (40.2 vs. 66.4%, p < 0.0001). The metabolic syndrome followed that same pattern: more prevalent in men (28.9 vs. 20.8%, p = 0.019) and less in women from San Antonio (27.1 vs. 30.9%, p < 0.0001). In subjects with the metabolic syndrome, most women had increased central adiposity (92.6% in San Antonio and 97.5% in Spain), and most men had either increased central adiposity or blood pressure (99.2% in San Antonio and 95.0% in Spain). Discussion: Contrary to men, the metabolic syndrome is more prevalent in Spanish women than in women from San Antonio with differences that mirror differences in central adiposity. Central adiposity and blood pressure may be used to exclude the metabolic syndrome. Considering recent secular trends in obesity, we predict there will be an increase in the prevalence of the metabolic syndrome in both populations in the coming years.     

Fungal infections of a colonial marine invertebrate: Diversity and morphological consequences

Summary Colonies of the bryozoan speciesHippodiplosia insculpta collected from Grandmother’s Cove (American Camp, San Juan Island, Washington, USA) were analyzed in view of pathologic growth patterns. The species produced giant buds that were filled with extracellular polymeric substances and a dense microbial biofilm consisting of bacteria and fungal hyphae. Fungi were isolated from the colonies and were identified asPenicillium expansum, Peniillium brevicompactum, Sclerotinia sclerotiorum, Acremonium breve, andCladosporium sphaerospermum. The results of this study indicate that the formation of giant buds in the bryozoan is a defense mechanism against fungal infection.     

Pre-mission invasion of Erodium cicutarium in California

Abstract. The California grassland is dominated by alien plant species. It is generally assumed that the invasion of aliens began with the initial introduction of livestock by Spanish missionaries in 1769. In this paper we present pollen evidence which indicates that Erodium cicutarium, a Mediterranean annual, was well established in the Santa Barbara region several years before the founding of the first California mission at San Diego in 1769. Historical evidence shows that it took the Spanish nearly a decade to develop a livestock base in California. Disturbance by livestock was therefore not a necessary prerequisite for invasion by alien plants. Historical and macrofossil evidence indicates that E. cicutarium invaded California from Baja California.     

Stratigraphic analysis of a fossil Neogoniolithon-capped patch reef and associated facies,San Salvador,Bahamas

An unusual Pleistocene patch reef is exposed in a coastal cliff at Grotto Beach, San Salvador, Bahamas. The reef is a coralline framestone constructed mainly by Porites astreoides together with a few large heads of Diploria strigosa and Montastrea annularis, and is capped by a dense thicket of Neogoniolithon strictum that is interpreted as marking the subtidal/intertidal boundary. The reef is flanked to the northeast by laminated to low-angle cross-laminated intraclastic grainstones and to the southwest by skeletal rudstone of reefal and interreefal derivation. Uranium-series dating of pure aragonite from a Diploria corallum yielded an age of 123 000±9000 years. Reef growth began on an erosional surface underlain by steeply crossbedded eolian grainstone. As the reef grew upward, it also grew laterally over adjacent penecontemporaneous subtidal sediments. The reef was eventually buried by 2.3 m of shallow subtidal and beach sediments that apparently prograded seaward during a highstand, or possibly while sea level was still rising. The shallow subtidal sediments are mainly peloidal, ooidal and skeletal grainstones that are pervasively bioturbated. The overlying beach facies comprises predominantly laminated, sparsely burrowed grainstone. The beach and shallow subtidal facies contain boulders of fine-grained laminated grainstone that are interpreted as storm-tossed blocks of beachrock. Living analogs of the Grotto Beach fossil reef lie off East Beach, San Salvador. Several of these have a flourishing cap of Neogoniolithon that extends above low-tide level and we believe that the Neogoniolithon cap of Grotto Beach reef did likewise. Wherever found in the stratigraphic record this facies should serve to identify the subtidal/intertidal boundary. The uppermost Pleistocene beach sediments associated with Grotto Beach fossil reef lie 5.8 m above present-day mean sea level, which ist strong evidence that this portion of San Salvador has undergone little subsidence since the Grotto Beach section was deposited.     

Investigating cultural heterogeneity in San Pedro de Atacama,northern Chile,through biogeochemistry and bioarchaeology

Individuals living in the San Pedro de Atacama oases and the neighboring upper Loa River Valley of northern Chile experienced the collapse of an influential foreign polity, environmental decline, and the appearance of a culturally distinct group during the Late Intermediate Period (ca. AD 1,100–1,400). We investigate cultural heterogeneity at the Loa site of Caspana through analyses of strontium and oxygen isotopes, cranial modification styles, and mortuary behavior, integrating biological aspects of identity, particularly geographic origins, with cultural aspects of identity manifested in body modification and mortuary behavior. We test the hypothesis that the Caspana population (n = 66) represents a migrant group, as supported by archeological and ethnographic evidence, rather than a culturally distinct local group. For Caspana archeological human tooth enamel, mean ⁸⁷Sr/⁸⁶Sr = 0.70771 ± 0.00038 (1σ, n = 30) and mean δ¹⁸O_c(V‐PDB) = ?3.9 ± 0.6‰ (1σ, n = 16); these isotopic data suggest that only one individual lived outside the region. Material culture suggests that the individuals buried at Caspana shared some cultural affinity with the San Pedro oases while maintaining distinct cultural traditions. Finally, cranial modification data show high frequencies of head shaping [92.4% (n = 61/65)] and an overwhelming preference for annular modification [75.4% (n = 46/61)], contrasting sharply with practices in the San Pedro area. Based on multiple lines of evidence, we argue that, rather than representing a group of altiplano migrants, the Caspana population existed in the region for some time. However, cranial modification styles and mortuary behavior that are markedly distinct from patterns in surrounding areas raise the possibility of cultural heterogeneity and cultural fissioning. Am J Phys Anthropol, 2009. © 2008 Wiley‐Liss, Inc.     

Genetic and historical evidence disagree on likely sources of the Atlantic amethyst gem clam Gemma gemma (Totten, 1834) in California

Aim Historical information about source populations of invasive species is often limited; therefore, genetic analyses are used. We compared inference about source populations from historical and genetic data for the oyster‐associated clam, Gemma gemma that invaded California from the USA Atlantic coast. Location Mid‐Atlantic (North Carolina, Maryland), Northeastern (New Jersey, New York, Massachusetts) and the California coasts (Elkhorn Slough, San Francisco Bay, Bolinas Lagoon, Tomales Bay, Bodega Harbor). Methods The documented history of transplantation of Eastern oysters to California was reviewed. Cytochrome c oxidase subunit I (COI) sequences from recent and archived clams were examined in a haplotype network. We used AMOVA to detect geographic genetic structure and a permutation test for significant reductions in diversity. Results Chesapeake Bay oysters were transplanted to New York prior to shipment to San Francisco Bay and from there to peripheral bays. Gemma in the Northeastern and Mid‐Atlantic regions were genetically differentiated. In California, populations in Bodega Harbor and Tomales Bay were genetically similar to those in the Mid‐Atlantic area while clams in San Francisco Bay, Elkhorn Slough and Bolinas Lagoon resembled populations in the Northeastern region. In California, genetic variation was not highest in San Francisco Bay despite greater magnitude of oyster plantings. Haplotypes varied over time in native and introduced populations. Main Conclusions Historical records and inferences from genetics agree that both Northeastern and Mid‐Atlantic regions were sources for Gemma in California. Only complex genetic hypotheses reconcile the strong segregation of haplotypes in California to the historical evidence of mixing in their proximate source (New York). These hypotheses include sorting of mixtures of haplotypes or selection in non‐native areas. Haplotype turnover in San Francisco and Massachusetts samples over time suggests that the sorting hypothesis is plausible. We suggest, however, that Gemma was introduced independently and recently to Tomales Bay and Bodega Harbor.     

Population morphometric variation of the endemic freshwater killifish, <Emphasis Type="Italic">Fundulus lima</Emphasis> (Teleostei: Fundulidae), and its coastal relative <Emphasis Type="Italic">F. parvipinnis</Emphasis> from the Baja California Peninsula,Mexico

The population morphometric variation of the endangered freshwater killifish (Fundulus lima) was evaluated and compared with that of its euryhaline coastal relatives (F. parvipinnis parvipinnis and F. p. brevis) on the basis of 384 specimens from the Baja California peninsula, Mexico. Forty five standardized body distances were compared by means of discriminant function analysis (DFA). Sixteen body distances were significant to distinguish two groups of populations for F. lima: a first group represented by the Bebelamas and San Javier basins, and second group composed by the basins of San Ignacio, La Purísima, San Luis, San Pedro and Las Pocitas. When all freshwater and coastal populations were compared, the southernmost population of F. lima (Las Pocitas) showed a higher morphometric similarity with the southern coastal subspecies (F. p. brevis), while another southern population (San Pedro) had an intermediate position between the freshwater and coastal forms. This study suggests the presence of five evolutionary units (three freshwater and two coastal) for the genus Fundulus in the Baja California peninsula.     

Genome‐wide Association Study and Follow‐up Analysis of Adiposity Traits in Hispanic Americans: The IRAS Family Study

We investigated candidate genomic regions associated with computed tomography (CT)–derived measures of adiposity in Hispanics from the Insulin Resistance Atherosclerosis Study Family Study (IRASFS). In 1,190 Hispanic individuals from 92 families 3 from the San Luis Valley, Colorado and San Antonio, Texas, we measured CT‐derived visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and visceral:subcutaneous ratio (VSR). A genome‐wide association study (GWAS) was completed using the Illumina HumanHap 300 BeadChip (～317K single‐nucleotide polymorphisms (SNPs)) in 229 individuals from the San Antonio site (stage 1). In total, 297 SNPs with evidence for association with VAT, SAT, or VSR, adjusting for age and sex (P < 0.001), were genotyped in the remaining 961 Hispanic samples. The entire Hispanic cohort (n = 1,190) was then tested for association, adjusting for age, sex, site of recruitment, and admixture estimates (stage 2). In stage 3, additional SNPs were genotyped in four genic regions showing evidence of association in stage 2. Several SNPs were associated in the GWAS (P < 1 × 10^?5) and were confirmed to be significantly associated in the entire Hispanic cohort (P < 0.01), including: rs7543757 for VAT, rs4754373 and rs11212913 for SAT, and rs4541696 and rs4134351 for VSR. Numerous SNPs were associated with multiple adiposity phenotypes. Targeted analysis of four genes whose SNPs were significant in stage 2 suggests candidate genes for influencing the distribution (RGS6) and amount of adiposity (NGEF). Several candidate loci, including RGS6 and NGEF, are associated with CT‐derived adipose fat measures in Hispanic Americans in a three‐stage genetic association study.     

The rapid evolution of self-fertility in Spartina hybrids (Spartina alterniflora × foliosa) invading San Francisco Bay, CA

Plant hybridization can lead to the evolution of invasiveness. We wished to determine whether hybrids between the largely self-sterile Atlantic Spartina alterniflora and California native S. foliosa had evolved self-fertility during their ca 30 year existence in San Francisco Bay, CA. In pollination experiments we found that neither of the parental species was self-fertile, nor were early generation hybrids. A large fraction of later generation hybrids were profusely self-fertile. Inbreeding depression was high in the parental species and early generation hybrids, but was much reduced in later generation hybrids—some even showed outbreeding depression. We found that populations of later generation hybrids and their seedling progeny were almost two-fold more homozygous than early generation hybrids, consistent with the evidence of increased selfing shown by our parentage analyses based upon 17 microsatellite markers. We posit that evolved self-fertility has contributed substantially to the rapid spread of hybrid Spartina in San Francisco Bay.     

Made in China: The Gods Go East

ABSTRACT

Jamie Uys's The Gods Must be Crazy and its sequel films are icons of South African entertainment, perceived both as hilarious comedy and blatant apartheid propaganda. Three further sequels, made from Hong Kong by Chinese directors, are hardly known in South Africa. These films are particularly interesting from a cultural point of view, as they portray Orientals (and white South Africans) from an Oriental perspective and San Bushmen from a position that is neither Western nor set in an apartheid/post-apartheid South African context. The current context of globalization in which cultures are expressed and negotiated creates an interesting space for the analysis of these “multicultural” films. This article examines these films especially, Crazy Safari, and discusses them in terms of responses from focus groups, one of Taiwanese viewers in Durban, and another of Kenyans in Kenya.     

Assessing natural infection with Zika virus in the southern house mosquito,Culex quinquefasciatus,during 2016 in Puerto Rico

The epidemic of Zika in the Western hemisphere has led to intense investigations of all species important in the transmission of Zika virus (ZikV), including putative mosquito vectors. Although evidence points to Stegomyia (= Aedes) (Diptera: Culicidae) mosquitoes as the primary vectors in nature among humans, there remains the possibility that other common mosquito species may be implicated in the rapid spread of the virus. Herein, field‐caught Culex quinquefasciatus (Diptera: Culicidae) collected during June 2016 in different neighbourhoods in San Juan, Puerto Rico were examined for the presence of natural infection with ZikV. Stegomyia aegypti (= Aedes aegypti) from the same locations were also analysed. None of the Cx. quinquefasciatus tested showed natural infection for ZikV, whereas S. aegypti tested positive at seven sites. The present results suggest that Cx. quinquefasciatus was not involved in the transmission of ZikV in San Juan, Puerto Rico in 2016.     

Effects of grazing and invasive grasses on desert vertebrates in California

Much of California's San Joaquin Valley is a desert and, like portions of other North American deserts, is experiencing an ecological shift from being dominated by ephemeral native forbs, with widely spaced shrubs, to fire-prone non-native annual grasses. Small terrestrial vertebrates, many of which are adapted to open desert habitats, are declining. One hypothesis is that the invasive plants contribute to the decline by altering vegetative structure. Although cattle may have originally been a factor in the establishment of these non-native plants, their grazing may benefit the terrestrial vertebrates by maintaining an open structure, especially during average or wet winters when the exotic grasses grow especially dense. We experimentally tested the effect of cattle grazing on invasive plants and a community of small vertebrates at a site in the southwestern San Joaquin Desert. We established and monitored 4 treatment (grazed) and 4 control (ungrazed) plots from 1997 to 2006, and assessed the abundances of blunt-nosed leopard lizards (Gambelia sila), giant kangaroo rats (Dipodomys ingens), short-nosed kangaroo rats (Dipodomys nitratoides nitratoides), and San Joaquin antelope squirrels (Ammospermophilus nelsoni), all of which are listed as threatened or endangered by state or federal agencies. We also recorded abundances of the non-protected western whiptail lizards (Aspidoscelis tigris), side-blotched lizards (Uta stansburiana), San Joaquin pocket mice (Perognathus inornatus inornatus), and Heermann's kangaroo rats (Dipdomys heermanni). Based on repeated measures analysis of variance (ANOVA) and a 0.05 alpha level, only Heermann's kangaroo rats showed a treatment effect; they were more abundant on the control plots. However, this effect could be accounted for by the natural re-establishment of saltbush (Atriplex spp.) on part of the study site. Saltbush return also favored western whiptail lizards and San Joaquin antelope squirrels. A regression analysis indicated that populations of blunt-nosed leopard lizard and giant kangaroo rat increased significantly faster in grazed plots than the ungrazed controls, and abundances of 6 of 8 species were negatively correlated with increased residual dry matter. With relaxed alpha values to decrease Type II error, populations of blunt-nosed leopard lizards (500% greater), San Joaquin antelope squirrels (85% greater), and short-nosed kangaroo rats (73% greater) increased significantly on grazed plots over the course of the study compared to ungrazed plots. We did not find grazing to negatively affect abundance of any species we studied. When herbaceous cover is low during years of below average rainfall in deserts and other arid areas, grazing may not be necessary to maintain populations of small vertebrates. However, if cattle grazing is closely monitored in space and time to minimize adverse effects on the habitat, it could be an effective tool to control dense stands of non-native grasses and benefit native wildlife. © 2011 The Wildlife Society.