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At least 37 records · Page 2Linked to original sources
PubMed2000

Higher-level phylogeny of the Therevidae (Diptera: insecta) based on 28S ribosomal and elongation factor-1 alpha gene sequences.

Therevidae (stilleto flies) are a little-known family of asiloid brachyceran Diptera (Insecta). Separate and combined phylogenetic analyses of 1200 bases of the 28S ribosomal DNA and 1100 bases of elongation factor-1alpha were used to infer phylogenetic relationships within the family. The position of the enigmatic taxon Apsilocephala Kröber is evaluated in light of the molecular evidence. In all analyses, molecular data strongly support the monophyly of Therevidae, excluding Apsilocephala, and the division of Therevidae into two main clades corresponding to a previous classification of the family into the subfamilies Phycinae and Therevinae. Despite strong support for some relationships within these groups, relationships at the base of the two main clades are weakly supported. Short branch lengths for Australasian clades at the base of the Therevinae may represent a rapid radiation of therevids in Australia.

Animals↗
PubMed2001

Phylogenetic analysis of partial sequences of elongation factor 1alpha identifies major groups of lice (Insecta: Phthiraptera).

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 1alpha 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.

Animals↗
PubMed2002

Simultaneous molecular and morphological analysis of braconid relationships (Insecta: Hymenoptera: Braconidae) indicates independent mt-tRNA gene inversions within a single wasp family.

We investigated the phylogeny of the Braconidae (Insecta: Hymenoptera) with a much expanded data set compared with that of previous attempts, employing 16S and 28S rDNA gene fragments, together with a suite of morphological characters, from 74 ingroup taxa. Most notably, parsimony analyses under a range of models recovered the Aphidiinae as sister group to the cyclostomes and the Ichneutinae as sister group to the microgastroids. The cyclostomes were recovered as a natural group only if certain, putatively misplaced genera (Mesostoa, Aspilodemon) were excluded from them. Further, mapping of rearrangement characters onto this phylogeny of the Braconidae indicated parallel inversions of the mt-tRNAD gene, with the two instances of inversion distinguishable by the presence or absence of an additional tRNA gene (tRNAH). This is the first report of a parallel inversion of a mt-tRNA gene and makes the Braconidae the first metazoan family to display both parallel inversions and translocations.

Animals↗
PubMed2006

Bioaccumulation and toxicity of 4-nonylphenol (4-NP) and 4-(2-dodecyl)-benzene sulfonate (LAS) in Lumbriculus variegatus (Oligochaeta) and Chironomus riparius (Insecta).

The discharge of surfactants, such as 4-nonylphenol (4-NP) and linear alkylbenzene sulfonates (LAS), into water bodies leads to accumulation of the chemicals in the sediments and may thus pose a problem to benthic organisms. To study the bioaccumulation of surfactants, Oligochaeta worm Lumbriculus variegatus was exposed to sediment-spiked, [14C]-labeled 4-NP and 4-(2-dodecyl)-benzene sulfonate (C12-LAS) in three different sediments (S1-S3). The sediments were characterized for organic carbon (OC) content and particle size distribution. The acute toxicity was examined by exposing L. variegatus and three to four instar Chironomus riparius (Insecta) larvae in water-only exposure to 4-NP and LAS at different concentrations. After 48-h exposure, lethal water concentrations (LC50) and lethal body residues (LBR50) were estimated using liquid scintillation counting. Chronic toxicity was evaluated in two different sediments by exposing first instar C. riparius larvae to sediment-spiked chemicals at different concentrations. After 10 days, the sublethal effects of surfactants were observed by measuring wet weight and head capsule length. Finally, another 10-day test was set up in order to measure the LAS body residues associated with sublethal effects in C. riparius in S2 sediment. The bioaccumulation test revealed that the bioaccumulation of both 4-NP and LAS increased as the sediment organic matter content decreased. It is assumed that the chemical binding to organic material decreased chemical bioavailability. The acute toxicity tests showed that L. variegatus was more tolerant of 4-NP, and C. riparius was more tolerant of LAS when based on water exposure concentration. The LBR-estimates revealed, however, that L. variegatus tolerated clearly higher tissue residues of both chemicals compared with C. riparius. Both chemicals had sublethal effects on C. riparius growth in sediment exposure, reducing larvae wet weight and head capsule size. 4-NP, however, showed an irregular dose-response pattern. The characteristics of the exposure media affected the bioaccumulation potential of both chemicals. Thus, exposure concentrations offered no prediction of body residue, and therefore it is proposed that organism body residue offered a more accurate dose-metric for chemical exposure than the chemical concentration of the environment.

Alkanesulfonic Acids↗
PubMed2004

Differences in straggling rates between two genera of dove lice (Insecta: Phthiraptera) reinforce population genetic and cophylogenetic patterns.

Differences in dispersal abilities have been implicated for causing disparate evolutionary patterns between Columbicola and Physconelloides lice (Insecta: Phthiraptera). However, no study has documented straggling (when lice are found on atypical hosts) rates within these lineages. We used the fact that the Galapagos Hawk, Buteo galapagoensis (Gould) (Falconiformes) feeds on the Galapagos Dove Zenaida galapagoensis Gould (Columbiformes) within an ecologically simplified setting. The Galapagos Dove is the only typical host of Columbicola macrourae (Wilson) and Physconelloides galapagensis (Kellogg and Huwana) in Galapagos. We quantitatively sampled and found these lice on both bird species. A DNA barcoding approach confirmed that stragglers were derived from Galapagos doves. We also collected a Bovicola sp. louse, likely originating from a goat (Capra hircus). On hawks, C. macrourae was significantly more prevalent than P. galapagensis. On doves, the two lice were equally prevalent and abundant. Differences in prevalence on hawks was a function of differences in straggling rate between lice, and not a reflection of their relative representation within the dove population. This provides further evidence that differences in dispersal abilities may drive differences in the degree of cospeciation in Columbicola and Phyconelloides lice, which have become model systems in evolutionary biology.

Animals↗
PubMed2004

Speciation by host-switching in pinyon Cinara (Insecta: Hemiptera: Aphididae).

Parasite-host cospeciation has received much attention as an important mechanism in the diversification of phytophagous insects. However, studies have shown that for certain taxa, it is not host fidelity but host-switching that plays the critical role in speciation. Cinara are aphids (Insecta: Hemiptera: Aphididae: Lachninae) that feed exclusively on the woody parts of conifers of the Cupressaceae and Pinaceae. They are unusual aphids because most Pinaceae play host to several species of Cinara. The aphids show relatively strong host fidelity, and as a consequence historically have been treated based on the taxonomy of their hosts. The historical paradigm of aphid evolution implies that Cinara species have radiated to different parts of the same host species and/or speciated with their host. Using mitochondrial cytochrome oxidase 1 and nuclear elongation factor 1-alpha DNA sequences, we performed molecular phylogenetic analysis of Cinara species, concentrating on those associated with pinyon pines in the southwestern USA. We determined that switching hosts has played a key role in the speciation of the genus, reflected in the polyphyly of pinyon-feeding Cinara. Furthermore, species sharing a common feeding site on different hosts were more closely related to each other than to those sharing the same host but at different feeding sites, suggesting that feeding site fidelity plays a more important role in speciation than does host fidelity in general. This study also elucidated the primary taxonomy of various species: it suggested that Cinara rustica Hottes is a junior synonym of C. edulis (Wilson) and that C. wahtolca Hottes represents two species on the two different pinyon pine species, Pinus edulis Englem. and P. monophylla Torr. & Frem.

Animals↗
PubMed2005

Gelechioidea (Insecta: Lepidoptera) systematics: a reexamination using combined morphology and mitochondrial DNA data.

Phylogenies of Gelechioidea (Insecta: Lepidoptera) historically have been in disagreement and definitions vary at the family and subfamily levels. Addition of new taxa or new characters drastically changes relationships indicating that current phylogenetic schemes require more investigation. This study is the first phylogenetic analysis of Gelechioidea to include molecular data. Here we present a combined analysis using Maximum Parsimony to investigate sister-group relationships within Gelechioidea. The addition of Cytochrome oxidase I and II to revised published morphological matrices gives 453 parsimony informative characters for the 42 taxa for which we have sequence data. The combined analysis resulted in two trees with mostly novel sister-group relationships. These results challenge current concepts of Gelechioidea, suggesting that traditional morphological characters that have united taxa may not be homologous structures and are in need of further investigation. A combination of morphological data with new molecular data will be the most robust method of study for Gelechioidea phylogenetics.

Animals↗
PubMed2006

Evolution of the planthoppers (Insecta: Hemiptera: Fulgoroidea).

The planthopper superfamily Fulgoroidea (Insecta: Hemiptera) comprises approximately 20 described insect families, depending on which classification is followed. Multiple competing hypotheses of fulgoroid phylogeny have been published, based on either morphological character coding or DNA sequence data; however, those hypotheses disagree in several key aspects regarding the evolution of planthoppers. The current paper seeks to test these hypotheses, including the Asche (Asche, M. 1987. Preliminary thoughts on the phylogeny of Fulgoromorpha (Homoptera Auchenorrhyncha). In: Proceedings of the 6th Auchenorrhyncha Meeting, Turin, Italy, 7-11 September, 1987, pp. 47-53.) hypothesis of a trend in ovipositor structure, which may be correlated with planthopper feeding ecology. Presented here are phylogenetic reconstructions of Fulgoroidea based on analysis of DNA nucleotide sequence data from four loci (18S rDNA, 28S rDNA, Histone 3, and Wingless) sequenced from 83 exemplar taxa representing 18 planthopper families and outgroups. Data sets were analyzed separately and in various combinations under the maximum parsimony criterion, and the total combined dataset was analyzed via both maximum parsimony and partitioned Bayesian criteria; results of the combined analyses were concordant across reconstruction paradigms. Relationships recovered suggest several major planthopper lineages, including: (1) Delphacidae+Cixiidae; (2) Kinnaridae+Meenoplidae; (3) Fulgoridae+Dictyopharidae; (4) Lophopidae+Eurybrachidae (possibly+Flatidae); (5) Ricaniidae+Caliscelidae (possibly+Tropiduchidae). Results also suggest the placement of Achilixiidae outside of Cixiidae and of Tettigometridae as one of the more recently diversified lineages within Fulgoroidea. The resulting phylogeny supports Asche's (1987) hypothesis of a functional trend in ovipositor structure across families.

Animals↗
PubMed2002

Evolution and phylogenetic information content of the ribosomal DNA repeat unit in the Blattodea (Insecta).

The organization, structure, and nucleotide variability of the ribosomal repeat unit was compared among families, genera, and species of cockroaches (Insecta:Blattodea). Sequence comparisons and molecular phylogenetic analyses were used to describe rDNA repeat unit variation at differing taxonomic levels. A reverse similar 1200 bp fragment of the 28S rDNA sequence was assessed for its potential utility in reconstructing higher-level phylogenetic relationships in cockroaches. Parsimony and maximum likelihood analyses of these data strongly support the expected pattern of relationships among cockroach groups. The examined 5' end of the 28S rDNA is shown to be an informative marker for larger studies of cockroach phylogeny. Comparative analysis of the nucleotide sequences of the rDNA internal transcribed spacers (ITS1 and ITS2) among closely related species of Blattella and Periplaneta reveals that ITS sequences can vary widely in primary sequence, length, and folding pattern. Secondary structure estimates for the ITS region of Blattella species indicate that variation in this spacer region can also influence the folding pattern of the 5.8S subunit. These results support the idea that ITS sequences play an important role in the stability and function of the rRNA cluster.

Animals↗
PubMed2002

The population genetics of host specificity: genetic differentiation in dove lice (Insecta: Phthiraptera).

Some species of parasites occur on a wide range of hosts while others are restricted to one or a few host species. The host specificity of a parasite species is determined, in part, by its ability to disperse between host species. Dispersal limitations can be studied by exploring the genetic structure of parasite populations both within a single species of host and across multiple host species. In this study we examined the genetic structure in the mitochondrial cytochrome oxidase I (COI) gene of two genera of lice (Insecta: Phthiraptera) occurring on multiple sympatric species of doves in southern North and Central America. One genus, Columbicola, is generally less host-specific than the other, Physconelloides. For both genera we identified substantial genetic differentiation between populations of conspecific lice on different host species, generally 10-20% sequence divergence. This level of divergence is in the range of that often observed between species of these two genera. We used nested clade analysis to explore fine scale genetic structure within species of these feather lice. We found that species of Physconelloides exhibited more genetic structure, both among hosts and among geographical localities, than did species of Columbicola. In many cases, single haplotypes within species of Columbicola are distributed on multiple host species. Thus, the population genetic structure of species of Physconelloides reveals evidence of geographical differentiation on top of high host species specificity. Underlying differences in dispersal biology probably explain the differences in population genetic structure that we observed between Columbicola and Physconelloides.

Animals↗
PubMed2003

Intracellular symbionts of sharpshooters (Insecta: Hemiptera: Cicadellinae) form a distinct clade with a small genome.

The leafhoppers (Insecta: Hemiptera: Cicadellidae) are the most species-rich group of invertebrates in which intracellular symbionts are usual. Here we present the first molecular characterization of bacteriome-associates in the leafhoppers, with focus on the subfamily Cicadellinae (sharpshooters). Phylogenetic analyses of 16S rDNA sequences from intracellular symbionts residing in the bacteriomes of five host species indicate that these symbionts form a well-defined clade within the gamma-3 Proteobacteria, consistent with an ancient colonization and strict vertical transmission. More extensive gene sequence information is reported for the symbiont of Homalodisca coagulata (Say). The genome size, as determined by pulsed field gel electrophoresis, is approximately 680 kb. This finding, when combined with published results for symbionts of aphids, ants, psyllids and tsetse flies, adds to an emerging pattern which suggests that bacteriome associates often descend from ancient infections by gamma Proteobacteria, and that these lineages have undergone pronounced genome reduction. A new genus and species name, 'Candidatus Baumannia cicadellinicola' (sp. nov.) is proposed for this newly characterized clade of symbiotic bacteria.

Animals↗
PubMed2000

Different mechanisms underlie phenotypic plasticity and interspecific variation for a reproductive character in drosophilids (Insecta: Diptera).

The insect ovary is a modular structure, the functional unit of which is the ovariole. Ovariole number is positively correlated with potential reproductive output. Among drosophilids (Insecta: Diptera), ovariole number shows both phenotypic plasticity and substantial interspecific and interpopulational variation. Here we examine the mechanistic connection between phenotypic plasticity and genetically fixed variation in ovariole number within the melanogaster species group. When a laboratory population of Drosophila melanogaster was reared under reduced food conditions, differences in ovariole number were entirely due to alterations in cell differentiation during the wandering stage at the very end of larval development. Cell growth and cell death were not affected. When these same flies were reared under a variety of temperatures, ovariole number differences arose during the latter half of the third (final) larval instar. Cell differentiation was affected, although cell number was not, and ovariole number differences were established before metamorphosis. In contrast, genetically fixed, interspecific and interpopulational variability in ovariole number was caused by alterations in the dynamics of cell differentiation and by cell number differences. Furthermore, the stages affected were different in different species and populations in the melanogaster species group, ranging from the first (D. sechellia) through the middle of the third (D. simulans and D. mauritiana) larval stage. Therefore, the mechanistic bases for plasticity-based variability are largely distinct from the mechanistic bases for interspecific and interpopulational variability. Our results suggest that phenotypic plasticity indicates evolutionary flexibility in underlying ontogenetic processes.

Animals↗
PubMed2006

Characteristics of the nuclear (18S, 5.8S, 28S and 5S) and mitochondrial (12S and 16S) rRNA genes of Apis mellifera (Insecta: Hymenoptera): structure, organization, and retrotransposable elements.

As an accompanying manuscript to the release of the honey bee genome, we report the entire sequence of the nuclear (18S, 5.8S, 28S and 5S) and mitochondrial (12S and 16S) ribosomal RNA (rRNA)-encoding gene sequences (rDNA) and related internally and externally transcribed spacer regions of Apis mellifera (Insecta: Hymenoptera: Apocrita). Additionally, we predict secondary structures for the mature rRNA molecules based on comparative sequence analyses with other arthropod taxa and reference to recently published crystal structures of the ribosome. In general, the structures of honey bee rRNAs are in agreement with previously predicted rRNA models from other arthropods in core regions of the rRNA, with little additional expansion in non-conserved regions. Our multiple sequence alignments are made available on several public databases and provide a preliminary establishment of a global structural model of all rRNAs from the insects. Additionally, we provide conserved stretches of sequences flanking the rDNA cistrons that comprise the externally transcribed spacer regions (ETS) and part of the intergenic spacer region (IGS), including several repetitive motifs. Finally, we report the occurrence of retrotransposition in the nuclear large subunit rDNA, as R2 elements are present in the usual insertion points found in other arthropods. Interestingly, functional R1 elements usually present in the genomes of insects were not detected in the honey bee rRNA genes. The reverse transcriptase products of the R2 elements are deduced from their putative open reading frames and structurally aligned with those from another hymenopteran insect, the jewel wasp Nasonia (Pteromalidae). Stretches of conserved amino acids shared between Apis and Nasonia are illustrated and serve as potential sites for primer design, as target amplicons within these R2 elements may serve as novel phylogenetic markers for Hymenoptera. Given the impending completion of the sequencing of the Nasonia genome, we expect our report eventually to shed light on the evolution of the hymenopteran genome within higher insects, particularly regarding the relative maintenance of conserved rDNA genes, related variable spacer regions and retrotransposable elements.

3' Untranslated Regions↗
PubMed2006

Co-cladogenesis spanning three phyla: leafhoppers (Insecta: Hemiptera: Cicadellidae) and their dual bacterial symbionts.

Endosymbioses are a major form of biological complexity affecting the ecological and evolutionary diversification of many eukaryotic groups. These associations are exemplified by nutritional symbioses of insects for which phylogenetic studies have demonstrated numerous cases of long-term codiversification between a bacterial and a host lineage. Some insects, including most leafhoppers (Insecta: Hemiptera: Cicadellidae), have more than one bacterial symbiont within specialized host cells, raising questions regarding the patterns of codiversification of these multiple partners and the evolutionary persistence of complex symbiotic systems. Previous studies reported the presence of two dominant symbiont types in a member of the leafhopper subfamily Cicadellinae (sharpshooters). In this study, 16S rRNA sequences were obtained and used to examine the occurrence and evolutionary relationships of the two dominant symbiont types across 29 leafhopper species. Candidatus Sulcia muelleri (Bacteroidetes) was detected in all leafhopper species examined, a finding that is consistent with a previous report of its ancient association with the Auchenorrhyncha (a grouping that includes leafhoppers, treehoppers, cicadas, planthoppers, and spittlebugs). Baumannia cicadellinicola (Proteobacteria), previously known from only five sharpshooter species, was found only in the sharpshooter tribes Cicadellini and Proconiini, as well as in the subfamily Phereurhininae. Mitochondrial and nuclear gene sequences were obtained and used to reconstruct host phylogenies. Analyses of host and symbiont data sets support a congruent evolutionary history between sharpshooters, Sulcia and Baumannia and thus provide the first strong evidence for long-term co-inheritance of multiple symbionts during the diversification of a eukaryotic host. Sulcia shows a fivefold lower rate of 16S rDNA sequence divergence than does Baumannia for the same host pairs. The term 'coprimary' symbiont is proposed for such cases.

Animals↗
PubMed1995

Microtubule organization and the distribution of gamma-tubulin in spermatogenesis of a beetle, Tenebrio molitor (Tenebrionidae, Coleoptera, Insecta).

The present study focuses on the restructuring of the microtubule (MT) cytoskeleton and microtubule-organizing centres (MTOCs) throughout spermatogenesis of a darkling beetle, Tenebrio molitor (Tenebrionidae, Coleoptera, Insecta). To this end, serial ultrathin sections through male germ cells were studied using transmission electron microscopy. Additionally, spindles and young spermatids were isolated from testes under MT-stabilizing conditions and doubly labeled with antibodies against beta- and gamma-tubulin. The latter is a tubulin isoform detected in MTOCs of a wide variety of species. The observations suggest that microtubules may be nucleated from sites with and without high gamma-tubulin content and that these sites do not necessarily possess canonical centrosomes. In a prominent cytoplasmic MT system of primary spermatocytes in prophase, microtubule nucleation apparently occurs in the absence of immunologically detectable gamma-tubulin. At the poles of meiotic spindles, MTs are directly inserted into gamma-tubulin-containing material and this connection is considered responsible for their nucleation. The interzone spindle MTs of telophase cells contain gamma-tubulin and this may confer stability to them. Finally, manchette MTs of spermatids originate in the vicinity of the acrosome precursor but are not inserted into this body. The acrosome precursor is surrounded by a membrane and is clearly detected by the antibody against gamma-tubulin.

Amino Acid Sequence↗
PubMed1983

The analysis of a protein-polymorphism. Evolution of monomeric and homodimeric haemoglobins (erythrocruorins) of Chironomus thummi thummi (Insecta, Diptera).

The evolutionary history of 12 Chironomus thummi thummi (CTT) haemoglobins of known primary structures was reconstructed by the maximum parsimony method. This reconstruction demonstrates that the 12 CTT haemoglobin lineages originated monophyletically from a common ancestor within early Insecta and have the lineage to monomeric blood worm haemoglobin as their closest sister group. It can be further deduced that the earliest ancestral CTT haemoglobins were monomers and that a branch to all extant dimeric CTT haemoglobins emerged later in phylogeny near the base of Chironomidae, but perhaps still before Chironomus itself evolved. This ancient, pre-Chironomus history suggests that among insect taxa, now lacking expressed globins, remnants of globin genes might exist as unexpressed pseudogenes. By the parameter of base replacement frequencies, CTT haemoglobins appear as relatively slow-evolving proteins, showing a preponderance of guanine in equilibrium adenine transitions at the first nucleotide position of the codons but not at the second. The most conservatively-evolving amino acid positions are haem contacts; the next most conservative are in interhelical contacts and interior positions involved in stabilization of tertiary structure. Further elucidation of the phylogenetic origins and adaptive evolution of the multiple haemoglobins found in Chironomus will be possible by the maximum parsimony method once haemoglobins or, in their absence, haemoglobin pseudogenes are sequenced in species throughout Chironomidae and related taxa.

Amino Acid Sequence↗
PubMed1989

Structure of a hemoglobin gene cluster and nucleotide sequence of three hemoglobin genes from the midge Chironomus thummi piger (Diptera, Insecta).

The aquatic larvae of the genus Chironomus (Diptera, Insecta) contain at least 12 different hemoglobin (Hb) variants in their hemolymph. In the present study we have analysed the structure and part of the nucleotide sequence of a Hb gene cluster cloned from the genomic DNA of Chironomus thummi piger. The cluster contains probably 6 different genes, separated by intergenic regions of various lengths. The nucleotide sequence of three putative Hb genes including the intergenic regions is presented. The inferred amino-acid sequences show clearly that two of these putative genes code for subvariants of the Hb variant VIIB. The third gene codes for a so far unknown Hb protein. As known already for other chironomid Hb genes, there are no intron sequences present in the coding regions.

Amino Acid Sequence↗
PubMed2003

Treatment of black-tailed prairie dog burrows with deltamethrin to control fleas (Insecta: Siphonaptera) and plague.

Burrows within black-tailed prairie dog (Cynomys ludovicianus) colonies on the Rocky Mountain Arsenal National Wildlife Refuge, Colorado, were dusted with deltamethrin insecticide to reduce flea (Insecta: Siphonaptera) abundance. Flea populations were monitored pre- and posttreatment by combing prairie dogs and collecting fleas from burrows. A single application of deltamethrin significantly reduced populations of the plague vector Oropsylla hirsuta, and other flea species on prairie dogs and in prairie dog burrows for at least 84 d. A plague epizootic on the Rocky Mountain Arsenal National Wildlife Refuge caused high mortality of prairie dogs on some untreated colonies, but did not appear to affect nearby colonies dusted with deltamethrin.

Animals↗