Rock Pocket Mouse Research Articles

The Magic School Bus Explores Human Evolution

It’s the longest field trip ever for Ms. Frizzle’s class! In the latest installment in the popular Magic School Bus series, a classroom activity involving the construction of family trees leads to a 3.5-billion-year excursion, tracing the human lineage from the primordial cell through the first vertebrates to mammals, primates, hominins, and, finally, Homo sapiens. “We may speak different languages, eat different food, make different art, and have different religions,” Ms. Frizzle observes toward the end of the journey. “But we are all human beings with the same family tree” (p. 45). (The message is reinforced by the inclusion on the field trip of a cousin of one of the students, visiting from China.) The students then work together to construct a “terrific”—and charming, if selective—phylogenetic chart.The approach of beginning with the familiar idea of a family tree and then introducing the idea of common ancestry is ideal for the intended readers, four through eight years old. The focus on following the human lineage is likely to reinforce the misconception that evolution is intrinsically progressive, which the occasional digression to highlight different lineages is not likely to be able to dispel, but the advantages outweigh the disadvantages. As in the Magic School Bus series in general, the pages (attractively illustrated by Bruce Degen) teem with corny jokes both verbal and visual, informative sidebars, and cameo appearances that invite further exploration—paleontology aficionados will particularly relish the opportunity to tell young readers about Pikaia, Tiktaalik, and gorgonopsids.The last few pages abandon the narrative approach for straightforward exposition, and here especially the young reader will need further information and explanation from a well-informed mentor. (It would have been nice for there to be a guide for teachers and parents to prepare them for these discussions.) The exposition begins with a sketch of the evidence for evolution, including the fossil record and its documentation of evolutionary transitions, anatomical homology (misleadingly labeled “body plans”), embryological homology, a gesture in the direction of molecular homology, and vestigial and rudimentary structures. It is particularly gratifying to see a reminder “Evolution is still at work!” with a brief treatment of the medical and agricultural relevance of evolution.Then natural selection is presented with a fictitious but realistic example. (The example involves adaptive melanism in a population of mice living on white and black sand beaches; a well-documented example of adaptive melanism involves a population of rock pocket mice, Chaetodipus intermedius, living inland on light substrate and dark lava.) The example is vivid and helpful, although it is awkward that the inheritability of the mice’s coloration is not initially mentioned: the reader is told only, “After a while, almost all the mice were light,” without any indication that the shift is generational (p. 52). The oversight is rectified on the following page—“nature selects, or chooses, which living things survive to pass on their traits to their babies” (p. 53)—but then it is necessary to reread the previous discussion.The discussion of natural selection is presented under the heading “How Does Evolution Work?” as if natural selection were the only process at work in evolution, which is inconsistent (since endosymbiosis is described earlier in the book) and inaccurate: describing natural selection as important would have been preferable. In any case, the discussion of natural selection is followed by a discussion of artificial selection. The order of explanation thus inverts that of the Origin, which introduces natural selection by first describing artificial selection, with which Darwin’s original readers were presumably more or less familiar. With increased urbanization, Cole and Degen’s readers are not so likely to be acquainted with artificial selection, so the point of discussing it (at the same length as natural selection) is obscure.Given the continuing popularity of the Magic School Bus franchise—including not only the books but also a number of video games, two television series, and, reportedly, a planned big-screen version with Elizabeth Banks as the beloved teacher—the book is sure to end up in the hands of children across the country. Wahoo! (as Ms. Frizzle would say). Asked in 2019 by PBS Newshour why she and Degen wanted to write a book about evolution, Cole replied, “A famous scientist [Theodosius Dobzhansky, writing in The American Biology Teacher] once said, ‘Nothing in biology makes sense except in the light of evolution.’ That really means that evolution is the story of life on Earth.” For anyone wanting to share that story with young readers, The Magic School Bus Explores Human Evolution will be a splendid start.

Sonoran Desert rodent abundance response to surface temperature derived from remote sensing

Nocturnal rodents play a key role in the Sonoran Desert ecosystem as consumers, prey and reservoirs of disease-yet rodent distribution remains poorly mapped. We use surface temperature extracted from the Landsat Thematic Mapper thermal infrared band to model rodent abundance obtained from trapping data at the Organ Pipe Cactus National Monument in southwest Arizona. We produce response curves that describe the effects of surface temperature on species abundance. Daytime surface temperature derived from images collected in June across thirty rodent trapping grids ranged from 318 K (45.0 °C) to 332 K (59.2 °C). Results show peak seasonal surface temperature splits high species abundances into two groups: Merriam's kangaroo rat, Arizona pocket mouse, desert pocket mouse and southern grasshopper mouse species prefer habitat characterized by higher surface temperatures; and white-throated wood rat, cactus mouse, rock pocket mouse and Bailey's pocket mouse species prefer habitat characterized by lower temperatures. Abundances for the high and low temperature habitat groupings correlate linearly with surface temperature (r = +0.66 and −0.75, respectively, p < 0.001). Surface temperature integrates multiple landscape characteristics (e.g. topography, vegetation cover and soil properties) that define the dominant habitats of ORPI rodents. These results prove that simple models can inform complex ecological processes.

Convergent Evolution During Local Adaptation to Patchy Landscapes.

Species often encounter, and adapt to, many patches of similar environmental conditions across their range. Such adaptation can occur through convergent evolution if different alleles arise in different patches, or through the spread of shared alleles by migration acting to synchronize adaptation across the species. The tension between the two reflects the constraint imposed on evolution by the underlying genetic architecture versus how effectively selection and geographic isolation act to inhibit the geographic spread of locally adapted alleles. This paper studies the balance between these two routes to adaptation in a model of continuous environments with patchy selection pressures. We address the following questions: How long does it take for a novel allele to appear in a patch where it is locally adapted through mutation? Or, through migration from another, already adapted patch? Which is more likely to occur, as a function of distance between the patches? What population genetic signal is left by the spread of migrant alleles? To answer these questions we examine the family structure underlying migration–selection equilibrium surrounding an already adapted patch, treating those rare families that reach new patches as spatial branching processes. A main result is that patches further apart than a critical distance will likely evolve independent locally adapted alleles; this distance is proportional to the spatial scale of selection (, where σ is the dispersal distance and s m is the selective disadvantage of these alleles between patches), and depends linearly on log(s m/μ), where μ is the mutation rate. This provides a way to understand the role of geographic separation between patches in promoting convergent adaptation and the genomic signals it leaves behind. We illustrate these ideas using the convergent evolution of cryptic coloration in the rock pocket mouse, Chaetodipus intermedius, as an empirical example.

Of Mice and Metaphysics: Natural Selection and Realized Population-Level Properties

In this paper, I answer a fundamental question facing any view according to which natural selection is a population-level causal process—namely, how is the causal process of natural selection related to, yet not preempted by, causal processes that occur at the level of individual organisms? Without an answer to this grounding question, the population-level causal view appears unstable—collapsing into either an individual-level causal interpretation or the claim that selection is a purely formal, statistical phenomenon. I argue that a causal account of realization provides an answer to the grounding question. By applying this account of realization to the natural selection of melanism in rock pocket mice, I show how an alternative, formal account of realization, favored by proponents of the statistical interpretation, misses biologically important features. More generally, this paper shows how metaphysical issues about realization normally discussed in the philosophy of mind apply to debates in philosophy of biology. Thus, it is a first step toward fleshing out the oft-noted similarities between debates in these areas.

The genetic basis of adaptation: lessons from concealing coloration in pocket mice

Recent studies on the genetics of adaptive coat-color variation in pocket mice (Chaetodipus intermedius) are reviewed in the context of several on-going debates about the genetics of adaptation. Association mapping with candidate genes was used to identify mutations responsible for melanism in four different populations of C. intermedius. Here, I review four main results (i) a single gene, the melanocortin-1-receptor (Mc1r), appears to be responsible for most of the phenotypic variation in color in one population, the Pinacate site; (ii) four or fewer nucleotide changes at Mc1r appear to be responsible for the difference in receptor function; (iii) studies of migration-selection balance suggest that the selection coefficient associated with the dark Mc1r allele at the Pinacate site is large; and (iv) different (unknown) genes underlie the evolution of melanism on three other lava flows. These findings are discussed in light of the evolution of convergent phenotypes, the average size of phenotypic effects underlying adaptation, the evolution of dominance, and the distinction between adaptations caused by changes in gene dosage versus gene structure.

Local adaptation in the rock pocket mouse (Chaetodipus intermedius): natural selection and phylogenetic history of populations

Elucidating the causes of population divergence is a central goal of evolutionary biology. Rock pocket mice, Chaeotdipus intermedius, are an ideal system in which to study intraspecific phenotypic divergence because of the extensive color variation observed within this species. Here, we investigate whether phenotypic variation in color is correlated with local environmental conditions or with phylogenetic history. First, we quantified variation in pelage color (n=107 mice) and habitat color (n=51 rocks) using a spectrophotometer, and showed that there was a correlation between pelage color and habitat color across 14 sampled populations (R2=0.43). Analyses of mtDNA sequences from these same individuals revealed strong population structure in this species across its range, where most variation (63%) was partitioned between five geographic regions. Using Mantel tests, we show that there is no correlation between color variation and mtDNA phylogeny, suggesting that pelage coloration has evolved rapidly. At a finer geographical scale, high levels of gene flow between neighboring melanic and light populations suggest the selection acting on color must be quite strong to maintain habitat-specific phenotypic distributions. Finally, we raise the possibility that, in some cases, migration between populations of pocket mice inhabiting different lava flows may be responsible for similar melanic phenotypes in different populations. Together, the results suggest that color variation can evolve very rapidly over small geographic scales and that gene flow can both hinder and promote local adaptation.

ECOLOGICAL GENETICS OF ADAPTIVE COLOR POLYMORPHISM IN POCKET MICE: GEOGRAPHIC VARIATION IN SELECTED AND NEUTRAL GENES

Patterns of geographic variation in phenotype or genotype may provide evidence for natural selection. Here, we compare phenotypic variation in color, allele frequencies of a pigmentation gene (the melanocortin-1 receptor, Mc1r), and patterns of neutral mitochondrial DNA (mtDNA) variation in rock pocket mice (Chaetodipus intermedius) across a habitat gradient in southern Arizona. Pocket mice inhabiting volcanic lava have dark coats with unbanded, uniformly melanic hairs, whereas mice from nearby light-colored granitic rocks have light coats with banded hairs. This color polymorphism is a presumed adaptation to avoid predation. Previous work has demonstrated that two Mc1r alleles, D and d, differ by four amino acids, and are responsible for the color polymorphism: DD and Dd genotypes are melanic whereas dd genotypes are light colored. To determine the frequency of the two Mc1r allelic classes across the dark-colored lava and neighboring light-colored granite, we sequenced the Mc1r gene in 175 individuals from a 35-km transect in the Pinacate lava region. We also sequenced two neutral mtDNA genes, COIII and ND3, in the same individuals. We found a strong correlation between Mc1r allele frequency and habitat color and no correlation between mtDNA markers and habitat color. Using estimates of migration from mtDNA haplotypes between dark- and light-colored sampling sites and Mc1r allele frequencies at each site, we estimated selection coefficients against mismatched Mc1r alleles, assuming a simple model of migration-selection balance. Habitat-dependent selection appears strong but asymmetric: selection is stronger against light mice on dark rock than against melanic mice on light rock. Together these results suggest that natural selection acts to match pocket mouse coat color to substrate color, despite high levels of gene flow between light and melanic populations.

Mammalian melanism: natural selection in black and white

Two recent papers on the molecular basis of melanism strengthen the chain of evidence linking genotype and phenotype in nature. Research on coat colour polymorphisms in rock pocket mice from differently coloured rock substrates provides a compelling example of the genetics of adaptation and the serendipitous nature of darwinian selection. Mutations in one gene, melanocortin-1-receptor, are perfectly associated with dark coat colour on black lava. Comparative sequence analysis shows that the same gene is involved in melanic polymorphism in some cats.

The genetic basis of adaptive melanism in pocket mice.

Identifying the genes underlying adaptation is a major challenge in evolutionary biology. Here, we describe the molecular changes underlying adaptive coat color variation in a natural population of rock pocket mice, Chaetodipus intermedius. Rock pocket mice are generally light-colored and live on light-colored rocks. However, populations of dark (melanic) mice are found on dark lava, and this concealing coloration provides protection from avian and mammalian predators. We conducted association studies by using markers in candidate pigmentation genes and discovered four mutations in the melanocortin-1-receptor gene, Mc1r, that seem to be responsible for adaptive melanism in one population of lava-dwelling pocket mice. Interestingly, another melanic population of these mice on a different lava flow shows no association with Mc1r mutations, indicating that adaptive dark color has evolved independently in this species through changes at different genes.

Ability of Dipodomys merriami and Chaetodipus intermedios to Locate Resource Distributions

The ability of Merriam's kangaroo rat ( Dipodomys merriami ) and the rock pocket mouse ( Chaetodipus intermedius ) to locate sandboxes with food was studied in a series of three experiments using large laboratory arenas (6.9 by 3.7 m). In the first experiment, D. merriami learned the location of sandboxes after 3 nights with the same food distribution; after 4 nights, C. intermedius still had not located these sandboxes. When the foraging area was enlarged (6.9 by 11.1 m), D. merriami again located the food patch by the third trial. The performances of C. intermedius improved, but did not match the accuracy of D. merriami . The final experiment determined whether kangaroo rats detected food patches by smell. Sandboxes were never located efficiently when odor was the only cue available to kangaroo rats. These results indicate that D. merriami was more capable of locating food patches than C. intemedius and that this ability was a function of learning rather than olfactory cues.

Description of a New Rock Pocket Mouse, Chaetodipus intermedius, from New Mexico

Description of a New Rock Pocket Mouse, Chaetodipus intermedius, from New Mexico

Morphologic Variation among Rock Pocket Mice (Chaetodipus intermedius) from New Mexico Lava Fields

-Intraspecific variation in external and cranial measurements of rock pocket mice (Chaetodipus intermedius) was evaluated using 312 adult specimens (145 males and 167 females). Males were larger than females for 8 of 16 characters examined, and significant geographic variation occurred in 15 characters for one or both sexes. Generally, largest means of male and female characters were from specimens representing the Carrizozo malpais; the smallest mice were from the Afton lava flows. Specimens from the Pedro Armendariz lava field and the nearby Fra Cristobal Range were the closest geographically and the most similar morphologically. Rock pocket mice (Chaetodipus intermedius) occur in northwestern Mexico and throughout much of Arizona and New Mexico (Hall, 1981). Of the 10 currently recognized subspecies of C. intermedius (Hall, 1981), three are confined to isolated black-lava outcrops, C. i. nigrimontis occurs on Black Mountain, Pima Co., Arizona; C. i. ater occupies the Carrizozo malpais, Lincoln and Otero Cos., New Mexico; and C. i. rupestris is found on the Afton lava flows, Dona Ana Co., New Mexico. In addition, an isolated population of C. intermedius inhabits the Pedro Armendariz lava field in Sierra and Socorro Cos., New Mexico (Weckerly, 1983). These geographic isolates differ markedly in coloration from populations of rock pocket mice in surrounding areas (Dice, 1929; Benson, 1932; Blossom, 1933; Weckerly, 1983). How much these populations differ morphologically from each other or from nearby populations has not been established. The restricted distribution and presumably intense natural selection for dark pelage coloration may also be associated with some selection for morphologic variation among the forms inhabiting lava fields. Best and James (1984) noted that some lava-dwelling rattlesnakes (Crotalus), in addition to being darker, were much smaller than other populations in New Mexico. Perhaps body size, as well as coloration, are affected by selection pressures on lava fields. However, Rogers and Schmidly (1981) found essentially no morphologic differentiation among similar populations of Neotoma albigula. To determine if populations of C. intermedius differed between lava fields and an adjacent rocky outcrop, we studied morphologic variation in specimens collected from three lava fields and one mountain range in south-central New Mexico. Our purposes were to investigate the degree of sexual dimorphism, amount and pattern of interlocality variation within each character, and phenetic relationships among populations. MATERIALS AND METHODS.-We analyzed 4 external and 12 cranial measurements (Fig. 1) for 312 adult Chaetodipus intermedius. Total length, tail length, hind foot length, and ear length were recorded to the nearest mm from the specimen tag. Nasal width and interparietal width were taken with an ocular micrometer in a stereo microscope at lOx, and the remaining cranial and mandible measurements were made to the nearest 0.1 mm using dial calipers. Specimens were NOVEMBER 27, 1985 THE SOUTHWESTERN NATURALIST 30(4):491-501 This content downloaded from 157.55.39.144 on Mon, 25 Jul 2016 04:07:31 UTC All use subject to http://about.jstor.org/terms The Southwestern Naturalist

Physiological studies on the rock pocket mouse, Perognathus intermedius

1. 1. Metabolism, thermoregulatory patterns, pulmocutaneous water loss and hibernation cycles were studied in the rock pocket mouse, Perognathus intermedius. 2. 2. The thermoneutral zone for P. intermedius was not evident when measurements of rate of oxygen consumption, VO 2, were made in April. However, the zone was from about 33 to 36°C when measurements were made in January. 3. 3. The average VO 2 was about 23 per cent higher in January than in April. 4. 4. At T a below 30°C, VO 2 increased at a rate of 0·2 and 0·22 ml/g. hr for every 1°C decrease during January and April respectively. The rate of increase in VO 2 in January was about 13 percent lower as compared to the rate of increase in April. 5. 5. At ambient temperature T a above 37°C, VO 2 increased during January and showed no appreciable change during April even at a T a above 40°C. 6. 6. The T re is labile even at T a of 30°C. T re ranges between 33 and 36°C, and changes in T re appear to be related to time of day and T a. Lethal T re is about 41°C, and the rate of hyperthermia is less rapid than in other species of heteromyids. 7. 7. The pulmocutaneous water loss increases with rising T a. Water loss is similar in P. intermedius to other species of Perognathus at T a of 20–30°C, but at T a above 30°C, P. intermedius evaporated more than P. californicus. 8. 8. Daily hibernation occurs spontaneously at T a below the lower critical temperature and can be induced by food restriction.

Responses of Merriam's Kangaroo Rat to Heat

Previous articleNext article No AccessResponses of Merriam's Kangaroo Rat to HeatM. K. Yousef and D. B. DillM. K. Yousef Search for more articles by this author and D. B. Dill Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by Volume 44, Number 1Jan., 1971 Article DOIhttps://doi.org/10.1086/physzool.44.1.30155550 Views: 20Total views on this site Citations: 15Citations are reported from Crossref Journal History This article was published in Physiological Zoology (1928-1998), which is continued by Physiological and Biochemical Zoology (1999-present). Copyright 1972 The University of ChicagoPDF download Crossref reports the following articles citing this article:Zenon J. Czenze, Ben Smit, Barry Jaarsveld, Marc T. Freeman, Andrew E. McKechnie Caves, crevices and cooling capacity: Roost microclimate predicts heat tolerance in bats, Functional Ecology 36, no.11 (Nov 2021): 38–50.https://doi.org/10.1111/1365-2435.13918Bernhard Paces, Barbara M. Waringer, Adi Domer, Darren Burns, Yoram Zvik, Michał S. Wojciechowski, Eyal Shochat, Nir Sapir, Ivan Maggini Evaporative Water Loss and Stopover Behavior in Three Passerine Bird Species During Autumn Migration, Frontiers in Ecology and Evolution 9 (Aug 2021).https://doi.org/10.3389/fevo.2021.704676 Randall L. Tracy and Glenn E. Walsberg Unappreciated Tolerance to High Ambient Temperatures in a Widely Distributed Desert Rodent, Dipodomys merriami R. L. Tracy and G. E. Walsberg, Physiological and Biochemical Zoology 73, no.66 (Jul 2015): 809–818.https://doi.org/10.1086/318105Virginia Hayssen, Robert C Lacy Basal metabolic rates in mammals: Taxonomic differences in the allometry of BMR and body mass, Comparative Biochemistry and Physiology Part A: Physiology 81, no.44 (Jan 1985): 741–754.https://doi.org/10.1016/0300-9629(85)90904-1Jan A. Randall Comparison of sandbathing and grooming in two species of kangaroo rat, Animal Behaviour 29, no.44 (Nov 1981): 1213–1219.https://doi.org/10.1016/S0003-3472(81)80072-3Jan A. Randall, Del D. Thiessen Seasonal activity and thermoregulation in Meriones unguiculatus: A gerbil's choice, Behavioral Ecology and Sociobiology 7, no.44 (Nov 1980): 267–272.https://doi.org/10.1007/BF00300666C.J. Gordon, J.Homer Fergusoni Role of dietary lipids in cold survival and changes in body composition in white mice, Journal of Thermal Biology 5, no.11 (Jan 1980): 29–35.https://doi.org/10.1016/0306-4565(80)90037-6Christopher J. Gordon, J.Homer Ferguson The relationship between body composition and survival time during acute cold exposure in white mice (Mus musculus), Cryobiology 15, no.44 (Aug 1978): 441–445.https://doi.org/10.1016/0011-2240(78)90063-9W.G Bradley, M.K Yousef, Irena M Scott Physiological studies on the rock pocket mouse, Perognathus intermedius, Comparative Biochemistry and Physiology Part A: Physiology 50, no.22 (Feb 1975): 331–337.https://doi.org/10.1016/0300-9629(75)90022-5 Bruce A. Wunder The Effect of Activity on Body Temperature of Ord's Kangaroo Rat (Dipodomys ordii), Physiological Zoology 47, no.11 (Sep 2015): 29–36.https://doi.org/10.1086/physzool.47.1.30155620L.J. Breyen, W.G. Bradley, M.K. Yousef Physiological and ecological studies on the chisel-toothed kangaroo rat, dipodomys microps, Comparative Biochemistry and Physiology Part A: Physiology 44, no.22 (Feb 1973): 543–555.https://doi.org/10.1016/0300-9629(73)90507-0H.M. Frankel, M.K. Yousef, R. Bayer, D.B. Dill Blood composition in normothermic and hyperthermic kangaroo rats Dipodomysmerriami and laboratory rats Rattusnorvegicus, Comparative Biochemistry and Physiology Part A: Physiology 43, no.44 (Dec 1972): 733–738.https://doi.org/10.1016/0300-9629(72)90142-9Mary Jo Hamilton, J.Homer Ferguson Effects of exercise and cold acclimation on the ventricular and skeletal muscles of white mice (Mus musculus)—I. Succinic dehydrogenase activity, Comparative Biochemistry and Physiology Part A: Physiology 43, no.44 (Dec 1972): 815–824.https://doi.org/10.1016/0300-9629(72)90152-1W.G. BRADLEY, M.K. YOUSEF Small Mammals in the Desert, (Jan 1972): 127–142.https://doi.org/10.1016/B978-0-12-774650-0.50015-XM.K. Yousef, D.B. Dill Daily cycles of hibernation in the kangaroo rat, Dipodomys merriami, Cryobiology 8, no.55 (Oct 1971): 441–446.https://doi.org/10.1016/0011-2240(71)90034-4

Northern Geographic Limits of Four Desert Rodents of the Genera Peromyscus, Perognathus, Dipodomys, and Onychomys in the Rio Grande Valley

Four species of desert rodents were studied in the Rio Grande Valley of New Mexico in an effort to detect the factor or factors excluding each one from areas north of their ranges. Their dis- tributions were analyzed in relation to climate, vegetation, soil texture, and biotic competition. The cactus mouse (Peromyscus eremicus) and rock pocket mouse (Perognathus intermedius) seem to be limited by temperature. Each is saxicolous and inhabits rocky outcrops as far north as certain isotherms for average annual maximal temperature, these being 71 F for P. eremicus and 69 F for P. intermedius. Occasionally the former inhabits nonrocky sites, but the lack of mesquite (Prosopis juliflora) seems to prevent this animal from occupying such areas as far north as the 71 F isotherm. Both Merriam's kangaroo rat (Dipodomys merriami) and the south- ern grasshopper mouse (Onychomys torridus) may be limited by intra- generic, interspecific competition. Each species has an affinity for a habitat characterized by compact soils and certain kinds of vegetation. Areas of such habitat become increasingly less abundant from the southern to the northern parts of the ranges of the two species. In these northern areas, Ord's kangaroo rat (Dipodomys *ordii) excludes Merriam's kangaroo rat from most choice sites, and the northern grass- hopper mouse ( Onychomys leucogaster) excludes the southern grass- hopper mouse from sites with suitable habitat.

Temperature and Light Synchronization Experiments with Circadian Activity Rhythms in Two Color Forms of the Rock Pocket Mouse

Previous articleNext article No AccessTemperature and Light Synchronization Experiments with Circadian Activity Rhythms in Two Color Forms of the Rock Pocket MouseMary C. Stewart, and William G. ReederMary C. Stewart Search for more articles by this author , and William G. Reeder Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by Volume 41, Number 2Apr., 1968 Article DOIhttps://doi.org/10.1086/physzool.41.2.30155445 Views: 2Total views on this site Citations: 11Citations are reported from Crossref Journal History This article was published in Physiological Zoology (1928-1998), which is continued by Physiological and Biochemical Zoology (1999-present). Copyright 1968 University of ChicagoPDF download Crossref reports the following articles citing this article:Ralph E. Mistlberger, Benjamin Rusak Circadian Rhythms in Mammals, (Jan 2011): 363–375.https://doi.org/10.1016/B978-1-4160-6645-3.00032-3Ralph E. Mistlberger, Benjamin Rusak Circadian Rhythms in Mammals: Formal Properties and Environmental Influences, (Jan 2005): 321–334.https://doi.org/10.1016/B0-72-160797-7/50034-3Peter Ruoff, Ludger Rensing Temperature effects on circadian clocks, Journal of Thermal Biology 29, no.7-87-8 (Oct 2004): 445–456.https://doi.org/10.1016/j.jtherbio.2004.07.004Ludger Rensing, Peter Ruoff TEMPERATURE EFFECT ON ENTRAINMENT, PHASE SHIFTING, AND AMPLITUDE OF CIRCADIAN CLOCKS AND ITS MOLECULAR BASES, Chronobiology International 19, no.55 (Jul 2009): 807–864.https://doi.org/10.1081/CBI-120014569Andrew J.P Francis, Grahame J Coleman Phase Response Curves to Ambient Temperature Pulses in Rats, Physiology & Behavior 62, no.66 (Dec 1997): 1211–1217.https://doi.org/10.1016/S0031-9384(97)00202-3David E. Davis Failure of temperature to entrain a circannual rhythm of mass in California ground squirrels (Spermophilus beecheyi), Journal of Interdisiplinary Cycle Research 18, no.11 (May 1987): 59–70.https://doi.org/10.1080/09291018709359933Hans G Erkert, Elke Rothmund Differences in temperature sensitivity of the orcadian systems of homoiothermic and heterothermic neotropical bats, Comparative Biochemistry and Physiology Part A: Physiology 68, no.33 (Jan 1981): 383–390.https://doi.org/10.1016/0300-9629(81)90065-7Bruce R. Bahnak, Kenneth R. Kramm The effects of temperature and photoperiod on activity in the red squirrel, Tamiasciurus hudsonicus ∗, Journal of Interdisiplinary Cycle Research 10, no.11 (Apr 1979): 51–56.https://doi.org/10.1080/09291017909359651W.G Bradley, M.K Yousef, Irena M Scott Physiological studies on the rock pocket mouse, Perognathus intermedius, Comparative Biochemistry and Physiology Part A: Physiology 50, no.22 (Feb 1975): 331–337.https://doi.org/10.1016/0300-9629(75)90022-5Patricia J. DeCoursey LD ratios and the entrainment of circadian activity in a nocturnal and a diurnal rodent, Journal of Comparative Physiology 78, no.33 (Jan 1972): 221–235.https://doi.org/10.1007/BF00697656Klaus Hoffmann Die relative Wirksamkeit von Zeitgebern, Oecologia 3, no.22 (Jan 1969): 184–206.https://doi.org/10.1007/BF00416981