Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| similarity of satilite dna properties in the order rodentia. | we have characterized satellite dnas from 9 species of kangaroo rat (dipodomys) and have shown that the hs-alpha and hs-beta satellites, where present, are nearly identical in all species as to melting transition midpoint (tm), and density in neutral cscl, alkaline cscl, and cs(2)so(4)-ag(+) gradients. however, the ms satellites exist in two internally similar classes. the satellite dnas from three other rodents were characterized (densities listed are in neutral cscl). the pocket gopher, thomom ... | 1977 | 561953 |
| response characteristics of cochlear nucleus neurons to vowel sounds. | most studies in auditory neurophysiology have utilized tonal stimuli to determine the coding properties of neurons in the cochlear nuclei. in this investigation of the kangaroo rat, cochlear nuclei, neuronal responses to vowel sounds, as well as tones, were studied. the vowel sounds, each about 40 msec in duration were: see article. five were linked together to form a 200 msec stimulus and various combinations of five vowel sounds provided us with 18 different stimuli. the results show that neur ... | 1977 | 835971 |
| the pineal complex and its relationship to other epithalamic structures. | the pineal complex of rodents is made up of a pineal gland which developmentally always originates from the area between the habenular and posterior commissure and a pineal sac which is continuous with the choroid plexus of the third ventricle. at the light-microscopic level, this sac appears to be identical to the choroid plexus. the pineal sac abuts the deep and superficial pineal glands of the golden hamster. in the pet mouse, gerbil, kangaroo rat, and chinese hamster, the sac is contiguous w ... | 1977 | 899706 |
| measurements on the kidneys and vasa recta of various mammals in relation to urine concentrating capacity. | maximum urine-concentrating capacity (ucc) differs widely among mammals of different species, being very high in some desert species (e.g. kangaroo rats) and very low in freshwater acquatic species (e.g. beaver). in this study, kidneys of 21 species of mammals from widely different habitats were studied in histological sections to determine whether differences in ucc can be attributed to differences in kidney structure. parameters studied included the ratio of medullary to cortical thickness, th ... | 1977 | 407772 |
| binding of anti-nucleoside antibodies reveals different classes of dna in the chromosomes of the kangaroo rat (dipodomys ordii). | 1977 | 70368 | |
| kangaroo rat cochlea: qualitatively and quantitatively unique features. | 1977 | 898499 | |
| dipodomydectes americanus gen. et sp. n. (acari: hypoderidae) from the kangaroo rat. | 1978 | 627953 | |
| the kangaroo rat as a model for type i decompression sickness. | this study involved 720 exposures of 70 kangaroo rats trapped in west texas and showed that decompression-induced tail biting in this animal provides a good animal model for marginal limb bends in man. that this phenomenon can be reversed by recompression and pathological examination of the tail both indicated that a similar mechanism is probably involved in kangaroo rats and humans. quantitatively, the most susceptible 20% of kangaroo rats can reproduce the no-stop decompression limits for man ... | 1978 | 734799 |
| [sleep in marsupio, the kangaroo rat (potorous apicalis)]. | 1978 | 693605 | |
| the endogenous stages of eimeria utahensis (protozoa: eimeriidae) in the kangaroo rat, dipodomys ordii. | the endogenous life cycle of eimeria utahensis is described from experimentally infected kangaroo rats, dipodomys ordii. the endogenous asexual cycle consisted of 4 generations of meronts. first-generation meronts were concentrated in the anterior third of the small intestine. the succeeding generations of meronts and the sexual stages were concentrated in the middle third of the small intestine. first-generation meronts had a mean diameter of 9.7 micrometer and contained 12 to 16 merozoites. se ... | 1978 | 627970 |
| wheel running of kangaroo rats, dipodomys merriami, as related to food deprivation and body composition. | kangaroo rats deprived of food ran themselves to death in 48 h in wheel cages. despite the loss of 14.5% of body weight the ratio of water to protein was the same after the run as it was in control rats. metabolic measurements at rest and in the running wheel and weight loss in the 48-h run were used to estimate fuels used and water expended. two-thirds of the initial amount of fat and 9% of the protein were metabolized. the terminal mean percentage of body fat was about twice that observed in r ... | 1978 | 627494 |
| a mechanism for resource allocation among sympatric heteromyid rodent species. | laboratory feeding experiments were conducted with dipodomys ordii and perognathus flavus in an attempt to discover a mechanism which might result in seed size selection. there was no marked difference in the proportions of four seed types collected whether the rodents foraged in the presence or absence of one another. however, analysis of the variability in weight of each of the seed types collected by the two species showed that when alone, the larger kangaroo rat was less effective at harvest ... | 1978 | 28309270 |
| reingestion of feces in rodents and its daily rhythmicity. | the ingestion of feces is widespread among rodent species and is an extensively employed component of the repertoire of feeding behaviors in some species. coprophagy is thus a significant consideration in the nutrition and dietary ecology of many rodents. as certain fecal pellets pass from the anus, they are taken up directly into the mouth, chewed, and swallowed. the nocturnally active herbivorous kangaroo rat dipodomys microps ingests about 1/4 of the feces it produces daily and the daily patt ... | 1979 | 28310297 |
| mechanical vs. ischemic mechanisms for decompression sickness. | we used 20 kangaroo rats to investigate the effect of exposure to low oxygen levels (0.11 atm 02 inspired partial pressure) prior to decompression from a steady-state condition. this hypoxia was found to afford significant protection against limb bends as simulated in those animals by tail biting. yet, it potentiated neurologic symptoms compared with a control exposure on air with the same level of nitrogen supersaturation. however the incidence of simulated limb bends in the same animals was th ... | 1979 | 464957 |
| preferential occurrence of sister chromatid exchanges at heterochromatin-euchromatin junctions in the wallaby and hamster chromosomes. | chromosomes of two mammalian species, the white-throated wallaby and the rat-like hamster, possessed large amounts of constitutive heterochromatin which is detectable as c bands. by making use of this character the frequency of sister chromatid exchanges (sces) was determined for the c band and the euchromatic regions of the chromosome. in both species, the distribution of sces in the euchromatin of chromosomes was found to be proportional to its metaphase length, while the number of sces locali ... | 1979 | 510085 |
| an anatomical study of the brains of dipodomys (mammalia: rodentia: heteromyidae). | whole brains and nissl-stained serial sections of 3 species of kangaroo rat (dipodomys spectabilis, d. ordii, d. merriami) were compared for interspecific differences. neuroanatomical variations were conservative in nature. examination of the cerebellum revealed possible differences in locomotion and ecology. dipodomys ordii exhibited more neurological evidence for increased specialization of the hindlimbs, while d. merriami had the least differentiated cerebellar surface, thereby suggesting mor ... | 1979 | 507367 |
| influence of hypothalamic and ambient temperatures on sleep in kangaroo rats. | unanesthetized, unrestrained kangaroo rats (dipodomys) were studied to examine the changes in the frequency and duration of sleep states caused by long-term manipulations of hypothalamic temperature (thy) at a thermoneutral (30 degrees c) and a low (20 degrees c) ambient temperature (ta). a cold stimulus present in either the hypothalamus or the skin decreased both the total sleep time (tst) and the ratio of paradoxical sleep (ps) to tst. at a low ta, tst, but not the ps-to-tst ratio, was increa ... | 1979 | 223451 |
| the 500 hz frequency-following potential in kangaroo rat: an evaluation with noise masking. | this study on kangaroo rat has shown that the volume-conducted 500 hz ffp can be recorded at stimulus levels which are near behavioral threshold. the response is a complex, double-peaked wave form, indicating that multiple brain stem sources are involved in its generation. the ffp wave form changes in a complex manner with intensity. recordings of the ffp in the presence of broadband noise demonstrate that the response is neural in origin at suprathreshold stimulus levels. the various configurat ... | 1980 | 6155254 |
| the distribution of angiotensin ii binding sites in rodent brain. | the distribution of specific angiotensin ii (aii) binding capacity of several brain regions, pituitary, and adrenals was determined in 6 rodent species namely rats, mice, hamsters, kangaroo rats, gerbils and degus. rats and mice had similar distributions with the highest levels of binding observed in the area postrema, septum and superior colliculi. low levels were seen in the cortex, cerebellum, striatum and hippocampus. other areas had intermediate levels. the distribution of aii binding in ge ... | 1981 | 6258713 |
| tactile discriminatory ability and foraging strategies in kangaroo rats and pocket mice (rodentia: heteromyidae). | a comparative study of seasonal food hoarding activity and tactile discriminatory ability in four species of heteromyid rodents (dipodomys panamintinus, d. merriami, perognathus longimembris, and p. formosus) was conducted in laboratory test arenas. animals were tested individually to determine their treatment of seed (white millet) and seed mimics (glass beads and gravel) offered as food. in general, all animals showed low levels of millet hoarding activity during winter months with higher leve ... | 1981 | 28309045 |
| the red function of phage lambda mediates the alteration of an interspersed repeated dna sequence from the kangaroo rat dipodomys ordii. | the kangaroo rat d. ordii is shown to contain an interspersed repeated sequence 3.25 kb in length. this sequence undergoes alteration (deletions) when cloned into a red+ lambda vector but is stable in a red- vector. using the red- clone it is shown that deletions are the result of the activity of the lambda red, or e. coli rece, recombination systems. mixed infection experiments demonstrate that this activity is acting in trans. the deletions appear to yield fragments of specific size, suggestin ... | 1982 | 6294479 |
| ultrastructure of pinealocytes of the kangaroo rat (dipodomys ordi). | the ultrastructure of the pinealocytes of the wild-captured ord kangaroo rat (dipodomys ordi) was examined. a homogeneous population of pinealocytes was present in the pineal gland of the kangaroo rat. the golgi apparatus, granular endoplasmic reticulum, mitochondria, lysosomes, dense-core vesicles, vacuoles containing a flocculent material and lipid droplets were consistent components of the pinealocyte cytoplasm, whereas infrequently-observed organelles included centrioles, multivesicular bodi ... | 1982 | 7127418 |
| seasonal variation in various blood indices of the kangaroo rat, dipodomys panamintinus. | 1. various blood indices in the panamint kangaroo rat revealed seasonal fluctuations. the red blood cell count during winter and summer averaged 7.2 +/- 1.0 x 10(6) and 9.2 +/- 0.2 x 10(6)/mm3 respectively. 2. the mean cell hemoglobin during winter and summer averaged 25 +/- 10.8 pg and 18.6 +/- 3.7 pg respectively. 3. these fluctuations may reveal a rapid rate of red blood cell destruction during winter in combination with a change in diet, concomitant to this, is an increase in mean cell hemog ... | 1982 | 6121650 |
| hormonal regulation of sandbathing in male kangaroo rats (dipodomys merriami). | detection of reproductive status from chemical signals at sandbathing loci was examined in merriam's kangaroo rat. castrated and intact males were attracted similarly to the sandbathing loci of four classes of scent donors: intact males, castrated males, estrous females, and nonestrous females. this suggested that reproductive status was not communicated to males at sandbathing loci. in a control test, castrated males were attracted to disturbed sand that contained no olfactory cues whereas inta ... | 1983 | 6626088 |
| coccidia from kangaroo rats (dipodomys spp.) in the western united states, baja california, and northern mexico with descriptions of eimeria merriami sp. n. and isospora sp. | 1983 | 6827438 | |
| experimental field evidence of interspecific aggression between two species of kangaroo rat (dipodomys). | the competitive coexistence of heteromyid rodents has been primarily ascribed to differential utilization of resources such as microhabitats and seeds. an examination of the use of space by the kangaroo rat dipodomys merriami indicates this species is aggressively subordinate to a larger species, dipodomys spectabilis and is excluded from the larger species home range during the crtical fall harvesting season. these experiments suggest that interspecific aggression may be involved in the coexist ... | 1983 | 25024151 |
| changes in the thermal characteristics of hypothalamic neurons during sleep and wakefulness. | the characteristics of the mammalian thermoregulatory system are dependent upon arousal state. during nrem sleep thermoregulatory mechanisms are intact but body temperature is regulated at a lower level than during wakefulness. in rem sleep thermoregulatory effector mechanisms are inhibited and thermal homeostasis is severely disrupted. thermosensitivity of neurons in the preoptic/anterior hypothalamus (poah) was determined for behaving kangaroo rats (dipodomys deserti) during electrophysiologic ... | 1984 | 6488008 |
| postpartum and lactational estrus: a comparative analysis in rodentia. | virgin rodents exhibiting cycling estrus have traditionally been used for comparative studies of reproductive behavior. however estrus occurs in other life-history contexts, some of which differ from cycling estrus (ce) in that (a) the female is disposed to behave both maternally and sexually and (b) they result in litter overlap (i.e., the simultaneous gestation and lactation of two litters). in this report, two of these other modes of estrus are examined, with emphasis on their evolutionary an ... | 1984 | 6478785 |
| coccidia from california kangaroo rats (dipodomys spp.). | 1985 | 4057012 | |
| hearing in two cricetid rodents: wood rat (neotoma floridana) and grasshopper mouse (onychomys leucogaster). | the audiograms of two wood rats and three grasshopper mice were determined with a conditioned avoidance procedure. the wood rats were able to hear tones from 940 hz to 56 khz at a level of 60 db (spl), with their best sensitivity of -3 db occurring at 8 khz. the hearing of the grasshopper mice ranged from 1.85 khz to 69 khz at 60 db (spl), with their best sensitivity of 9 db also occurring at 8 khz. these results support the relation between interaural distance and high-frequency hearing and bet ... | 1985 | 3899497 |
| thermoregulatory responses to photoperiod by kangaroo rats (dipodomys ordii): influence of night lighting on nonshivering thermogenesis and resting metabolism. | the influence of photoperiod on resting oxygen consumption and nonshivering thermogenesis of winter-acclimatized kangaroo rats was determined by exposing freshly captured animals to 10-week controlled photoperiod treatments. three treatments were employed: 1) long days (ld) = 16l:8d, 2) short days (sd) = 8l:16d, and 3) short days interrupted with 15 min light at midnight (sdl). thermoneutral oxygen consumption was uninfluenced by treatment, and posttreatment values were not different from pretre ... | 1985 | 4056675 |
| helminths of sympatric populations of kangaroo rats (dipodomys ordii) and grasshopper mice (onychomys leucogaster) from the high plains of eastern new mexico. | during a 1-yr period 124 dipodomys ordii and 92 onychomys leucogaster were trapped from the same locality and were examined for helminths. only 1 cestode species (catenotaenia linsdalei) was recovered from d. ordii, whereas o. leucogaster was infected with 2 nematoda (litomosoides carinii, mastophorus muris), 2 cestoda (hymenolepis citelli, and 1 unknown), and 1 acanthocephalan (moniliformis clarki) species. all represent new host and distribution records. | 1985 | 4057002 |
| lack of gonadal control of the dorsal gland and sandbathing in male and female bannertail kangaroo rats, (dipodomys spectabilis). | previous studies have demonstrated gonadal control of mammalian scent glands; castration leads to reduced scent-marking rates and smaller gland sizes. i investigated whether gonadal hormones control the size of the dorsal gland (a specialized sebaceous gland) and sandbathing as a scent-marking behavior in adult male and female bannertail kangaroo rats (dipodomys spectabilis). gland sizes of males and females were similar in all age classes, except adult males with larger body weights had proport ... | 1986 | 3957263 |
| competitive release in microhabitat use among coexisting desert rodents: a natural experiment. | competitive release among desert rodents on sand dunes of differing species richness was examined in the great basin and mohave deserts, usa. expansions in microhabitat use were exhibited by the kangaroo rats dipodomys ordii and d. merriami (granivorous heteromyid rodents, weighing 49 and 42 g, respectively) as the number of coexisting heteromyid species decreased geographically. perognathus longimembris, the only common small heteromyid species (7 g) exhibited no competitive release. this may b ... | 1986 | 28311364 |
| the sequence of the 3.3-kilobase repetitive element from dipodomys ordii suggests a mechanism for its amplification and interspersion. | dna from the kangaroo rat, dipodomys ordii, contains a 3.3-kb, highly repeated sequence that is interspersed throughout the genome in small tandem clusters. one 3.3-kb unit has been cloned into pbr322 and the nucleotide sequence determined. the clone used was shown to be representative of the bulk of such sequences found in the genomic dna. the sequence contains 10 homologous subunits each ca. 260 bp in length. comparison of these to one another yielded a 258-bp consensus sequence containing a 3 ... | 1987 | 3041011 |
| [karyological characteristics of cell sublines of the kidney of the kangaroo rat and of skin fibroblasts of the indian muntjac]. | a study was made of the karyotypic structure of sublines derived from the kangaroo rat's kidney (nbl-3) and skin fibroblasts of the indian muntjac, available in the cell culture bank of the institute of cytology acad. sci. ussr. a comparative karyologic analysis was made of subline nbl-3 both contaminated with mycoplasma (nblk) and decontaminated with antibiotics (nbld). authentic differences in cell distribution according to chromosome number in nblk and nbld variants were shown. modal numbers ... | 1988 | 3176180 |
| radionuclide transport from soil to air, native vegetation, kangaroo rats and grazing cattle on the nevada test site. | between 1970 and 1986 the nevada applied ecology group (naeg), u.s. department of energy, conducted environmental radionuclide studies at weapons-testing sites on or adjacent to the nevada test site. in this paper, naeg studies conducted at two nuclear (fission) sites (ns201, ns219) and two nonnuclear (nonfission) sites (area 13 [project 57] and clean slate 2) are reviewed, synthesized and compared regarding (1) soil particle-size distribution and physical-chemical characteristics of 239 + 240pu ... | 1988 | 3198397 |
| kangaroo rat locomotion: design for elastic energy storage or acceleration? | mechanical stresses (force/cross-sectional area) acting in muscles, tendons and bones of the hindlimbs of kangaroo rats (dipodomys spectabilis) were calculated during steady-speed hops and vertical jumps. stresses were determined from both high-speed ciné films (light and x-ray) and force plate recordings, as well as from in vivo tendon force recordings. stresses in each hindlimb support element during hopping (1.6-3.1 m s-1) were generally only 33% of those acting during jumping (greater than o ... | 1988 | 3204333 |
| regulation of plasma antidiuretic hormone in the dehydrated kangaroo rat (dipodomys spectabilis m.). | a sensitive and specific radioimmunoassay was used to measure plasma antidiuretic hormone (plasma arginine vasopressin, pavp) concentrations in a conscious desert-adapted mammal, the banner-tailed kangaroo rat (dipodomys spectabilis; 131 +/- 2.3 g body mass), during normal hydration and in response to progressive dehydration. simultaneous measurements of pavp and plasma osmolality (posm) in these experiments permitted determination of the hypothalamo-neurohypophyseal system-osmoreceptor set poin ... | 1988 | 3360285 |
| muscle forces during locomotion in kangaroo rats: force platform and tendon buckle measurements compared. | the muscle forces and stresses occurring during normal locomotor activity in kangaroo rats are compared with the peak isometric force developed by the same muscles in situ. two methods were used simultaneously to determine the stresses (force/cross-sectional area) acting in the ankle extensors during steady-speed hopping and during jumps when animals were startled: a direct measurement using a force buckle surgically implanted around a tendon; and an indirect measurement using a force platform/c ... | 1988 | 3209966 |
| genomic structure and sequence variation of a 3.3-kb repeat dna element of the kangaroo rat, dipodomys ordii. | the genomic structure and sequence variation of a 3.3-kb repeat dna element, representing 5% of the genome of the kangaroo rat dipodomys ordii, has been investigated. most of the repeats are arranged in tandem arrays of 50 kb or more. thirteen randomly selected genomic clones have been mapped with twelve restriction enzymes. the frequency of sequence divergence in the genomic clones is 0.5%. the clone maps and the genomic structure studies have permitted the characterization of a number of varia ... | 1988 | 3215518 |
| [effect of cultivation conditions on the karyotype structure of a cell subline of the kangaroo rat kidney]. | variations in cultivation conditions were found to exert influence on the distribution of cells for chromosome number by changing the modal class. the change of the hmem medium for the emem medium during 2-6 passages results in the appearance of a new modal class with 16 chromosomes. the change in the chromosome number is preferably due to the loss of one x chromosome within the main structural variant of the karyotype (msvk). on the other hand, the change of the hmem medium for the f12 medium d ... | 1988 | 3245098 |
| vertical distribution of soil removed by four species of burrowing rodents in disturbed and undisturbed soils. | burrow volumes were determined in disturbed and undisturbed soils for four species of rodents in southeastern idaho. comparisons were made between soil types for the average volume and the proportion of the total volume of soil excavated from 10-cm increments for each species, and the relative number of burrows and proportion of total soil removed from beneath the minimum thickness of soil covers over buried low-level radioactive wastes. burrows of montane voles (microtus montanus) and deer mice ... | 1988 | 3280518 |
| preferred speeds in terrestrial vertebrates: are they equivalent? | terrestrial animals have 'preferred speeds' within each gait, that are used much more frequently than others for moving along the ground. energy costs reach minimal values at these speeds within each gait. in this study we asked whether these speeds are mechanically equivalent among different animals (i.e. speeds where the same levels of peak muscle stress occur). if so, this would help in establishing a link between the energetics and the mechanics of the active muscles at these speeds, providi ... | 1988 | 3209967 |
| the effects of owl predation on the foraging behavior of heteromyid rodents. | researchers have documented microhabitat partitioning among the heteromyid rodents of the deserts of north america that may result from microhabitat specific predation rates; large/bipedal species predominate in the open/risky microhabitat and small/quadrupedal species predominate in the bush/safer microhabitat. here, we provide direct experimental evidence on the role of predatory risk in affecting the foraging behavior of three species of heteromyid rodents: arizona pocket mouse (perognathus a ... | 1988 | 28312021 |
| effects of a low op dose on seed/bead discrimination in the kangaroo rat, dipodomys. | 1989 | 2758144 | |
| consumption and mortality of the white-footed mouse (rodentia: muridae) and ord's kangaroo rat (rodentia: heteromyidae) when fed carbaryl-bran grasshopper (orthoptera) bait. | two species of wild rodents (ord's kangaroo rat, dipodomys ordii woodhouse, and the white-footed mouse, peromyscus leucopus rafinesque) were fed 0, 2, and 20% (ai) by weight concentrations of carbaryl-bran grasshopper bait in the laboratory to determine whether the bait would be consumed, the total quantity of bait consumed within a specified period, whether mortality would occur, and whether bait would be consumed if other foods were readily available. consumption tests showed that bait ingesti ... | 1990 | 2126269 |
| spatial and temporal continuity of kangaroo rat populations shown by sequencing mitochondrial dna from museum specimens. | the advent of direct sequencing via the polymerase chain reaction (pcr) has opened up the possibility of molecular studies on museum specimens. here we analyze genetic variation in populations over time by applying pcr to dna extracted from museum specimens sampled from populations of one species over the last 78 years. included in this study were 43 museum specimens of the panamint kangaroo rat dipodomys panamintinus from localities representing each of three geographically distinct subspecies. ... | 1990 | 2120448 |
| the effects of delta-9-tetrahydrocannabinol on actin microfilaments. | fluorescence staining with rhodamine phalloidin specific for f-actin was employed to examine the effects of delta-9-tetrahydrocannabinol (thc) on the distribution of microfilaments in kangaroo rat epithelial cells (ptk2) and rabbit aortic endothelial cells (rae). ptk2 cells were more sensitive to thc treatment than rae cells. exposure of ptk2 cells to 10 microm thc for 2 h disrupted the microfilament network. after treatment with 20 microm thc for 2 h there was a loss of cell-to-cell contact bet ... | 1990 | 2175259 |
| development and evolution of the carotid circulation in geomyoid rodents in relationship to their craniomorphology. | the diversity in cranial morphology of living geomyoids, including pocket gophers (thomomys), spiny pocket mice (heteromys and liomys), desert pocket mice (chaetodipus and perognathus), and kangaroo rats and mice (dipodomys and microdipodops) is accompanied by only a few differences in their cephalic arterial circulation. the principal difference is the origin of the pterygopalatine artery, which serves the orbit and rostrum. in dipodomyines and perognathines it originates as a stapedial branch ... | 1990 | 2338717 |
| the influence of seed apparency, nutrient content and chemical defenses on dietary preference in dipodomys ordii. | physical, nutritional and defensive qualities of seeds differ in the extent to which they influence granivore preference. in a study aimed to quantifying those differences, ord's kangaroo rats (dipodomys ordii) were found to prefer the seeds of just three of twenty-nine species: cryptantha crassisepala, oryzopsis hymenoides and salsola kali. oryzopsis hymenoides was most preferred during the early plant growth season (april-july); preference for s. kali peaked during late (august-november) and d ... | 1990 | 28312708 |
| control of a desert-grassland transition by a keystone rodent guild. | twelve years after three species of kangaroo rats (dipodomys spp.) were removed from plots of chihuahuan desert shrub habitat, density of tall perennial and annual grasses had increased approximately threefold and rodent species typical of arid grassland had colonized. these were just the most recent and drmatic in a series of changes in plants and animals caused by experimental exclusion of dipodomys. in this ecosystem kangaroo rats are a keystone guild: through seed predation and soil disturba ... | 1990 | 17734708 |
| dispersal and genetic structure in kangaroo rats. | we used spatial autocorrelation of allele frequencies to examine local structure in a population of bannertailed kangaroo rats for which wright's isolation-by-distance model seems applicable, and for which we can estimate neighborhood size based on 10 years of data on demography and dispersal. the uniform dispersion and strong philopatric tendencies of this species provide a test case for the idea that restricted dispersal can lead to local genetic structure in small mammals. whether we consider ... | 1991 | 28564057 |
| wood rats and kangaroo rats: potential reservoirs of the lyme disease spirochete in california. | the etiologic agent of lyme disease, borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner, was isolated repeatedly from dusky-footed wood rats, neotoma fuscipes baird, and california kangaroo rats, dipodomys californicus merriam, in northern california. all animals were collected in a region endemic for lyme disease but for which the natural reservoir of b. burgdorferi was unknown. similar attempts to isolate spirochetes from lizards, other species of rodents, jack rabbits, and deer ... | 1991 | 1875357 |
| parasitic and phoretic arthropods of the elephant-eared and the santa cruz kangaroo rats. | the parasitic and phoretic arthropods of the elephant-eared kangaroo rat (dipodomys elephantinus) and santa cruz kangaroo rat (d. venustus) are reported; most of these represent new host records. thirteen of 14 (93%) of d. elephantinus and 11 of 12 (92%) of d. venustus had 11 and nine arthropod species, respectively. larval and nymphal stages of the tick dermacentor occidentalis were the most prevalent parasite (77%) on d. elephantinus whereas the mesostigmatid mite androlaelaps fahrenholzi was ... | 1991 | 2067062 |
| spatial memory and adaptive specialization of the hippocampus. | the hippocampus plays an important role in spatial memory and spatial cognition in birds and mammals. natural selection, sexual selection and artificial selection have resulted in an increase in the size of the hippocampus in a remarkably diverse group of animals that rely on spatial abilities to solve ecologically important problems. food-storing birds remember the locations of large numbers of scattered caches. polygynous male voles traverse large home ranges in search of mates. kangaroo rats ... | 1992 | 1384199 |
| structure in a desert rodent community: use of space around dipodomys spectabilis mounds. | in an earlier paper (bowers et al. 1987) we reported patterns of microhabitat use by desert rodents among 0.25-ha plots where seeds were added or certain rodent species removed. we used the results to make inferences about the spatial organization of the whole rodent community. here we change our focus to test for spatial usage patterns at a smaller (within-plot) scale. specifically, we examine to what extent spatial use varies with proximity to mounded burrows of the large kangaroo rat, dipodom ... | 1992 | 28313058 |
| effects of kangaroo rat exclusion on vegetation structure and plant species diversity in the chihuahuan desert. | long-term (1977-90) experimental exclusion of three species of kangaroo rats from study plots in the chihuahuan desert resulted in significant increases in abundance of a tall annual grass (aristida adscensionis) and a perennial bunch grass (eragrostis lehmanniana). this change in the vegetative cover affected use of these plots by several other rodent species and by foraging birds. the mechanism producing this change probably involves a combination of decreased soil disturbance and reduced pred ... | 1993 | 28313292 |
| fleas (siphonaptera) infesting giant kangaroo rats (dipodomys ingens) on the elkhorn and carrizo plains, san luis obispo county, california. | the giant kangaroo rat, dipodomys ingens (merriam), has a limited distribution in the san joaquin valley, ca. because of reductions in its geographic range, largely resulting from humans, the species was listed as an endangered species in 1980 by the california fish and game commission. as part of a study of the community ecology of southern california endangered species, including d. ingens, we were able to make flea collections from the rats when they were trapped and marked for population stu ... | 1993 | 8433341 |
| spongistatin 1, a highly cytotoxic, sponge-derived, marine natural product that inhibits mitosis, microtubule assembly, and the binding of vinblastine to tubulin. | a highly cytotoxic macrocyclic lactone polyether has been isolated from a spongia species and named spongistatin 1. with l1210 murine leukemia cells an ic50 value for cell proliferation of 20 pm was obtained, and an increase in the mitotic index concordant with the decrease in cell number was observed. kangaroo rat kidney ptk1 cells were examined by indirect immunofluorescence with a spongistatin 1 concentration that caused 50% reduction in cellular protein (0.3 nm) and with a 10-fold higher con ... | 1993 | 8232226 |
| genetic diversity among borrelia burgdorferi isolates from wood rats and kangaroo rats in california. | twenty-nine borrelia burgdorferi isolates, obtained from dusky-footed wood rats (neotoma fuscipes) and california kangaroo rats (dipodomys californicus) in california, were analyzed genetically. chromosomal dna was examined by restriction endonuclease analysis (rea) and gene probe restriction fragment length polymorphism. pulsed-field gel electrophoresis was used to analyze the plasmid profiles of the isolates. rea, the method with the greatest discrimination, disclosed 24 distinct restriction p ... | 1993 | 7905880 |
| hearing in prairie dogs: transition between surface and subterranean rodents. | behavioral audiograms were determined for four black-tailed and one white-tailed prairie dogs (cynomys ludovicianus and c. leucurus) using a conditioned avoidance procedure. the hearing of black-tailed prairie dogs ranges from 29 hz to 26 khz and that of the white-tailed prairie dog from 44 hz to 26 khz (at sound pressure levels of 60 db). both species have good low-frequency hearing, especially black-tailed prairie dogs which can hear as low as 4 hz and are more sensitive than any other rodent ... | 1994 | 8188546 |
| natural space-use patterns and hippocampal size in kangaroo rats. | the size of the hippocampus, a forebrain structure that processes spatial information, correlates with the need to relocate food caches by passerine birds and with sex-specific patterns of space use in microtine rodents. the influences on hippocampal anatomy of sexual selection within species, and natural selection between species, have not yet been studied in concert, however. here we report that natural space-use patterns predict hippocampal size within and between two species of kangaroo rats ... | 1994 | 7987661 |
| spatial memory in the desert kangaroo rat (dipodomys deserti). | desert kangaroo rats (dipodomys deserti) forage for seed distributed in patches in the desert environment and may remember patch locations. in experiment 1, 7 desert kangaroo rats that had discovered the location of a plastic token in 1 box accurately dug for a token hidden in the same location in a 2nd identical box. results of experiment 2 indicated that the rats primarily remembered the spatial location of the token within the box in relation to extramaze objects and the walls of the experime ... | 1994 | 8174344 |
| recruitment of antigenic gamma-tubulin during mitosis in animal cells: presence of gamma-tubulin in the mitotic spindle. | it has been claimed repeatedly that gamma-tubulin is exclusively localized at the spindle poles in mitotic animal cells, where it plays a role in microtubule nucleation. in addition to this localization, we have observed a gamma-tubulin-specific staining of the mitotic spindle in several animal cells (human, kangaroo rat, mouse, chinese hamster, xenopus and drosophila) using five polyclonal antibodies raised against unique gamma-tubulin sequences and four different fixation protocols. in hela an ... | 1994 | 7876350 |
| spatial population structure in the banner-tailed kangaroo rat, dipodomys spectabilis. | i attempted to characterize spatial units of local dynamics and dispersal in banner-tailed kangaroo rats (dipodomys spectabilis), to determine if spatial structure influenced population dynamics in the way predicted by current metapopulation models. d. spectabilis exhibited a hierarchical spatial structure. "local populations" that appeared as discrete entities on a scale of kilometers were subdivided into clusters of mounds on a scale of meters. this structure, however, cannot be characyerized ... | 1994 | 28307040 |
| effects of competition, colonization, and extinction on rodent species diversity. | analyses of long-term experimental data from the chihuahuan desert revealed that species diversity of other rodents was higher on plots from which kangaroo rats (dipodomys spp.) had been removed. the difference was due to consistently higher colonization and lower extinction probabilities of small granivorous rodents in the absence of competitively dominant kangaroo rats. the results of this ecosystem experiment demonstrate the importance of both competitive exclusion and metapopulation dynamics ... | 1995 | 7846530 |
| elastic and length-force characteristics of the gastrocnemius of the hopping mouse (notomys alexis) and the rat (rattus norvegicus). | the aim of this study was to compare the contractile and series elastic properties of terrestrial mammals that use bipedal versus quadrupedal gaits. the gastrocnemius muscle of the hopping mouse (body mass 30.2 +/- 2.4 g, mean +/- s.d.) and the rat (313 +/- 10.7 g) were compared with data from the literature for the wallaby and the kangaroo rat to distinguish scaling effects and locomotion-related effects on muscle properties. contractile length-force properties and series elastic stiffness were ... | 1996 | 8691113 |
| [the effect of the mycoplasma contamination of 2 kidney cell sublines from the kangaroo rat on their karyotypic structure]. | the karyotypic variability has been investigated for two cell sublines of rat kangaroo kidney cultured for 40-160 days after contamination with acholeplasma laidlawii, strain pg-8. the contaminated cultures did not differ from non-contaminated ones in cell distribution for chromosome number. the majority of cells of subline nbl-3-11 with modal number of chromosomes displayed the main structural variant of the karyotype (svk)--2+2+2+2+2+1; in subline nbl-3-17 the main svk being 3+3+3+3+3+2. a com ... | 1996 | 8768552 |
| no sex difference occurs in hippocampus, food-storing, or memory for food caches in black-capped chickadees. | a number of recent studies have described sex differences in the relative size of the hippocampus that are associated with sex differences in the use of space. voles, kangaroo rats, and cowbirds all exhibit a sex difference in relative size of the hippocampal formation that is correlated with a sex difference in spatial behaviour. we wished to determine whether sex differences in the size of the hippocampus occur in the absence of a difference in the use of space, and whether the previously desc ... | 1996 | 8883812 |
| [the genotoxic effect of ciprofloxacin on cultured cells from the kangaroo rat kidney and on skin fibroblasts from the indian muntjac]. | the genotoxicity of an antibiotic ciprofloxacin (cf) in doses of 10, 25, 50 and 100 mkg/ml under its short-term (6-48 h) and long-term (15-30 days) action on sublines of rat kangaroo kidney, nbl-3-11, and indian muntjak skin fibroblasts has been studied. the emergence of genotoxic effect depends on the dose and time of ciprofloxacin action on both the sublines, but the degree of this effect does not depend on these parameters directly. ciprofloxacin exerts no influence on cell distribution for c ... | 1996 | 9019897 |
| gastric trichobezoar in a banner-tailed kangaroo rat (dipodomys spectabilis). | a male, wild-caught kangaroo rat developed anorexia and wasting. the animal was euthanized and a gastric trichobezoar found at necropsy. the paucity of information regarding the clinical medicine of this species is a hindrance to those charged with the care of kangaroo rats. gastric trichobezoar should be considered as a differential diagnosis in cases of anorexia in kangaroo rats. | 1996 | 8938627 |
| reservoir competence of four chaparral-dwelling rodents for borrelia burgdorferi in california. | aspects of the reservoir competence of four rodents for the lyme disease spirochete, borrelia burgdorferi, were evaluated in california. rodents were live-trapped and ear-punch biopsies were cultured during each season. a second set of biopsies was cultured from representative individuals after 2-3 weeks of captivity and the results of culturing biopsies taken on both dates were compared with the results of feeding ixodes pacificus larvae on hosts xenodiagnostically. the prevalence of infections ... | 1996 | 8651378 |
| ixodes (ixodes) jellisoni and i. (i.) neotomae (acari:ixodidae): descriptions of the immature stages from california. | nymphal and larval stages of ixodes (ixodes) jellisoni cooley & kohls and i. (i.) neotomae cooley are described for the first time. these 2 tick species occur only in the western united states, predominantly in california. the primary host for i. jellisoni is the california kangaroo rat, dipodomys californicus (merriam); that for i. neotomae is the dusky-footed woodrat, neotoma fuscipes baird. the etiologic agent of lyme disease borrelia burgdorferi johnson, schmidt, hyde, steigerwalt & brenner ... | 1996 | 8667376 |
| hemorrhagic gastritis in free-living rodents in idaho. | between february 1992 and march 1994, four species of rodent from the snake river birds of prey area near boise, idaho (usa) were necropsied. hemorrhagic gastritis was observed in 16 of 131 townsend's ground squirrels (spermophilus townsendii), one of 11 ord's kangaroo rats (dipodomys ordii) and the one great basin pocket mouse (perognathus parvus) evaluated. no lesions were observed in 14 white-footed deer mice (peromyscus maniculatus). tissue from one townsend's ground squirrel was negative fo ... | 1996 | 9359067 |
| effects of bannertail kangaroo rat mounds on small-scale plant community structure. | the effects of bannertail kangaroo rat (dipodomys spectabilis) mounds and associated soil-surface disturbance on plant species composition and diversity in the chihuahuan desert were examined with multivariate analysis. kangaroo rat mounds created disturbance gaps and contributed to local species diversity by creating microhabitats that supported unique plant communities. these microhabitats supported populations of species that were relatively rare in surrounding areas. the diversity observed a ... | 1996 | 28307650 |
| kangaroo rat bone compared to white rat bone after short-term disuse and exercise. | kangaroo rats (dipodomys ordii) were used to study the effects of confinement on mechanical properties of bone with a long range objective of proposing an alternative to the white rat model for the study of disuse osteoporosis. kangaroo rats exhibit bipedal locomotion, which subjects their limbs to substantial accelerative forces in addition to the normal stress of weight bearing. we subjected groups of kangaroo rats and white rats (rattus norvegicus) to one of two confinement treatments or to a ... | 1996 | 8759284 |
| polyclonal antibodies against human gamma-tubulin stain centrioles in mammalian cells from different tissues. | rabbit polyclonal antibodies were raised against the c-terminal fragment (amino acid residues 318-451) of human gamma-tubulin. these antibodies were used to stain cultured cells of various tissues (epithelium, nervous tissue, fibroblasts) from different animals (human, monkey, pig, rat, kangaroo rat, mouse, hamster, chicken, triton). the antibodies specifically stained centrioles in the interphase and mitotic cells of mammals, but not birds (chicken) or amphibians (newt). in the interphase cells ... | 1997 | 9225254 |
| cheek pouch capacities and loading rates of heteromyid rodents. | rodents of the family heteromyidae are proficient gatherers and hoarders of seeds. a major component of their adaptive specialization for harvesting and transporting seeds is their spacious, fur-lined cheek pouches. precise measurements of cheek pouch capacities are essential if ecologists are to understand the foraging ecology, possible constraints on locomotion patterns, and competitive relationships of heteromyid rodents. to measure the size of these cheek pouches and the rate at which animal ... | 1997 | 28307290 |
| population structure of dipodomys ingens (heteromyidae): the role of spatial heterogeneity in maintaining genetic diversity. | the giant kangaroo rat, dipodomys ingens (heteromyidae), is an endangered rodent that inhabits approximately 3% of its estimated historic range. its current distribution is centered in two geographic areas, situated about 150 km apart, in south-central california. we sequenced a 293 base-pair fragment at the 5' end of the control region in 95 giant kangaroo rats from nine localities to examine the genetic structure of extant populations. we determine that mutations in this section of the control ... | 1997 | 28565504 |
| mechanisms for the keystone status of kangaroo rats: graminivory rather than granivory? | graminivory by kangaroo rats (dipodomys spp.) was investigated as a potential mechanism for the keystone role of these rodents in the dynamics of desert grasslands. experiments confirmed that ord's kangaroo rats (dipodomys ordii) cut and consumed a large proportion of the tillers of three chihuahuan desert tussock-forming grass species. field observations indicated that the characteristically cut grass tillers were absent from all-rodent and medium-sized kangaroo rat exclosures, but were frequen ... | 1997 | 28308138 |
| kangaroo rats exhibit spongiform degeneration of the central auditory system similar to that found in gerbils. | kangaroo rats develop spongiform degeneration of the central auditory system similar to that seen in the gerbil. light microscopic and transmission electron microscopic study of the cochlear nucleus and auditory nerve root (anr) of dipodomys deserti and d. merriami show that spongiform lesions develop in dendrites and oligodendrocytes of the cochlear nucleus and in oligodendrocytes of the anr that are morphologically indistinguishable from those extensively described in the mongolian gerbil, mer ... | 1997 | 9119769 |
| seismic communication between the burrows of kangaroo rats, dipodomys spectabilis. | banner-tailed kangaroo rats, dipodomys spectabilis, footdrum to produce substrate-borne and airborne acoustic energy. previous studies show that they communicate territorial ownership via airborne footdrumming signals. the research reported here used simulated footdrum patterns generated by an artificial 'thumper' to address the question of whether kangaroo rats communicate through seismic components of these acoustic signals. with microphones suspended in sealed burrows, we found that airborne ... | 1997 | 9373957 |
| sound-power collection by the auditory periphery of the mongolian gerbil meriones unguiculatus: iii. effect of variations in middle-ear volume. | the effects of variations in middle-ear cavity size on hearing sensitivity in the mongolian gerbil are predicted by computing the effect on acoustic power input to the middle ear. acoustic power collection from a diffuse sound field was computed from measurements of the middle-ear input impedance and external-ear radiation impedance and mathematical models of the middle and external ear presented in the first two papers of this series [j. acoust. soc. am. 92, 157-177 (1992); j. acoust. soc. am. ... | 1997 | 9104016 |
| botfly (diptera:oestridae) parasitism of ord's kangaroo rats (dipodomys ordii) at suffield national wildlife area, alberta, canada. | during field study of ord's kangaroo rat (dipodomys ordii) at suffield national wildlife area, alberta, canada, a high prevalence of parasitism by botfly (diptera: oestridae) larvae was observed. botflies have not previously been documented as parasites of kangaroo rats. botfly parasitism could have a significant impact on the growth, survival, and reproduction of ord's kangaroo rat, which is considered a vulnerable species in canada. therefore, it is important to investigate how botfly parasiti ... | 1997 | 9267398 |
| genome composition in venezuelan spiny-rats of the genus proechimys(rodentia, echimyidae). i. genome size, c-heterochromatin and repetitive dnas in situ hybridization patterns. | the genome sizes of the venezuelan spiny-rats proechimys guairae guairae (2n = 48) and p. trinitatis (2n = 62) were evaluated and proved to be 12.5 +/- 0.5 pg and 12.6 +/- 0.3 pg respectively, the highest so far recorded among mammals; also the c-heterochromatin (32.7%, coefficient of variation [cv] 3.8 and 35.8%, cv 4.4) and gc (44.2%, cv 2.7 and 43.6%, cv 2.9) contents are very high. highly repetitive (rep) dnas were isolated from restriction enzyme digested genomic dnas of both species. the i ... | 1997 | 9345903 |
| species-specific footdrumming in kangaroo rats: dipodomys ingens, d. deserti, d. spectabilis | footdrumming was compared in three allopatric species of kangaroo rat, dipodomysfrom three habitats. analysis of footdrumming recordings revealed species-specific patterns of drumming ranging from single thumps to individual footdrumming signatures. the desert kangaroo rat, d. desertidrums single thumps spaced 0.25-0.30 s apart that are sometimes introduced with a short footroll. the giant kangaroo rat, d. ingensdrums long footrolls that can average over 100 drums at 18 drums/s. the banner-taile ... | 1997 | 9398370 |
| maternal presence and rearing condition affect responses to a live predator in kangaroo rats (dipodomys heermanni arenae). | experiment 1 compared the responses of wild-caught adult and captive-born adult and juvenile kangaroo rats (dipodomys heermanni arenae) to a live snake. wild-caught adult rats were less active and monitored the snake more than during a control condition; captive-born juvenile rats did not behave differently during snake and control tests. snake-naive adult rats behaved more like the wild-caught adult rats, but not on all measures. in experiment 2, pups were tested at 25 and 50 days of age in 4 c ... | 1997 | 9419881 |
| small mammal survival and trapability in mark-recapture monitoring programs for hantavirus. | following the 1993 hantavirus pulmonary syndrome (hps) epidemic in the south-western united states, mammalogists and epidemiologists instituted long-term studies to monitor population density and prevalence of infection in rodents which constitute the reservoir for sin nombre virus (snv). in this study, field techniques used in sampling small mammals for snv infection were evaluated to determine if trapping and handling protocols were having significant effects on future trapability or mortality ... | 1998 | 9476220 |
| comparative morphometry of mammalian central auditory systems: variation in nuclei and form of the ascending system. | the volumes of the ten largest subcortical auditory nuclei were measured individually in a sample of 53 mammals, including 16 australian and four american marsupials. the nuclear sizes relative to the total of subcortical auditory tissue were normalized and then analyzed individually for statistically reliable deviations. the overall form of the entire system of ten nuclei and two nuclear sub-systems (cochlear nuclei, superior olives) were also analyzed for similarities and notable deviations am ... | 1998 | 9491274 |
| life history of ixodes (ixodes) jellisoni (acari: ixodidae) and its vector competence for borrelia burgdorferi sensu lato. | ixodes (ixodes) jellisoni cooley & kohls, a nonhuman biting and little known tick, is one of 4 members of the i. ricinus complex in the united states. a localized population of i. jellisoni inhabiting a grassland biotope in mendocino county, ca, was studied from 1993 to 1997. rodent trapping in all seasons revealed that the only host of both immature and adult i. jellisoni was the heteromyid rodent dipodomys californicus merriam. field investigations suggested that i. jellisoni is nidicolous in ... | 1999 | 10337104 |
| prevalence of cutaneous evaporation in merriam's kangaroo rat and its adaptive variation at the subspecific level. | previous estimates suggested that ventilatory evaporation constitutes the major source of water loss in kangaroo rats (dipodomys spp.). we quantified rates of water loss in merriam's kangaroo rat (dipodomys merriami) and demonstrate the degree to which acclimation to a particular thermal and hydric environment plays a role in the intraspecific variation in water loss evident in this species. we draw the following conclusions: (1) that water loss varies intraspecifically in merriam's kangaroo rat ... | 2000 | 10648219 |
| characterization of microsatellite loci in bannertailed and giant kangaroo rats, dipodomys spectabilis and dipodomys ingens. | 2000 | 10792713 | |
| unappreciated tolerance to high ambient temperatures in a widely distributed desert rodent, dipodomys merriami. | a long-held assertion has been that nocturnality is an escape mechanism for many nocturnal desert rodents because of limited tolerances to heat. to test this claim, we used a treadmill to examine the tolerances to high ambient temperatures (t(a)'s) of one subspecies of desert rodent, merriam's kangaroo rat, dipodomys merriami merriami, from contrasting environments. we simultaneously measured body temperature (t(b)), evaporative water loss, and metabolic rates at an ecologically relevant speed ( ... | 2000 | 11121354 |
| length control of primary cilia: analysis of monociliate and multiciliate ptk1 cells. | lengths of primary cilia in cultured ptk1 cells, on both a population basis and within individual (multiciliate) cells, have been compared. the latter examines the degree of discrepancy between cilia arising within the same cell and using a common precursor pool, on the hypothesis that a better correlation would be expected between cilia issuing from the same centrosome than between those in the population in general. to obtain accurate et plentiful measurements, a 'flow-fixation' technique was ... | 2000 | 11374436 |
| influence of small-scale disturbances by kangaroo rats on chihuahuan desert ants. | banner-tailed kangaroo rats (dipodomys spectabilis) are prominent ecosystem engineers that build large mounds that influence the spatial structuring of fungi, plants, and some ground-dwelling animals. ants are diverse and functionally important components of arid ecosystems; some species are also ecosystem engineers. we investigated the effects of patch disturbances created by d. spectabilis mounds on ant assemblages in a chihuahuan desert grassland in southern new mexico by using pitfall traps ... | 2000 | 28308216 |
| food caching and differential cache pilferage: a field study of coexistence of sympatric kangaroo rats and pocket mice. | ecologists studying sympatric heteromyid rodents have sought evidence for species differences in primary foraging abilities and preferences and/or behavioural responses to predation risk in order to explain coexistence. the present field study was conducted to test the hypothesis that another factor may be involved, namely differences in caching patterns, which may result in differences in vulnerability to pilferage. we examined differences between kangaroo rats (dipodomys merriami) and pocket m ... | 2001 | 28547403 |
| geographic patterns of genetic differentiation within the restricted range of the endangered stephens' kangaroo rat dipodomys stephensi. | using mtdna variation in the kangaroo rat dipodomys stephensi, we found no support for the hypothesis that a species with an historically restricted range will exhibit low levels of genetic polymorphism and little genetic structure. dipodomys stephensi has long been restricted to a few interior coastal valleys in southern california encompassing an area of approximately 70 x 40 km; however, we found high levels of genetic variation over much of its range and significant genetic structure both wi ... | 2001 | 11475059 |
| integration of genotoxic and population genetic endpoints in biomonitoring and risk assessment. | genetic ecotoxicology is a multifaceted discipline that examines the effects of xenobiotic compounds on the structure and function of dna. this paper discusses the role of genetic ecotoxicology in environmental biomonitoring and risk assessment. genetic ecotoxicology may include somatic effects (e.g., dna damage) or population genetic effects (changes in genetic diversity or gene frequencies). traditionally, genetic ecotoxicology studies have focused on either one of these sub-disciplines, but i ... | 2001 | 11501436 |
| urea excretion in white rats and kangaroo rats as influenced by excitement and by diet. | reprinted from the american journal of physiology, vol. 181, no.1, april, 1955. | 2001 | 11274249 |