Termite Soil Eating in Kirindy Sifakas (Madagascar): Proposing a New Proximate Factor

2005 ◽  
Vol 76 (2) ◽  
pp. 119-122 ◽  
Author(s):  
Ivan Norscia ◽  
Valentina Carrai ◽  
Brunello Ceccanti ◽  
Silvana M. Borgognini Tarli
Keyword(s):  
Proximate Factor ◽  
Soil Eating

Temperature as a Proximate Factor in Orientation Behavior

1977 ◽  
Vol 34 (5) ◽  
pp. 734-739 ◽  
Author(s):  
William W. Reynolds
Keyword(s):  
Temperature Response ◽  
Biotic Interactions ◽  
Niche Differentiation ◽  
Behavioral Thermoregulation ◽  
Size Segregation ◽  
Ecological Value ◽  
Thermal Requirements ◽  
Prey Location ◽  
Proximate Factor ◽  
Species Specific

Temperature serves as a proximate factor (cue, guidepost, sign stimulus, or directive factor) affecting locomotor responses of fishes. Although temperature can also serve as an ultimate ecological factor, as in behavioral thermoregulation, nonthermal factors may in some cases provide the ultimate adaptive or ecological value of a temperature response; some examples are habitat selection, intraspecific size segregation, interspecific niche differentiation, isolating mechanisms, predator avoidance, prey location, escape reactions, and migrations (thermoperiodic, diel, seasonal, spawning). Conversely, nonthermal variables such as light intensity or water depth may act as accessory proximate factors in thermoregulation. In spawning migrations, thermal requirements of eggs and larvae may take precedence over the (often different) preferenda or optima of adults. Although thermal responses of fishes are largely innate and species specific, ontogenetic and other changes can occur. Since temperature can serve as an unconditioned reinforcer in operant conditioning, thermal responses are not limited to simple kineses or taxes. Nonthermal factors such as photoperiod, circadian rhythms, currents, social and biotic interactions, stresses, infections, or chemicals can affect thermal responses, and may account for some lack of conformity between laboratory preferenda and field distributions and behaviors. Key words: thermoregulation, orientation, preferendum, selection, preference, avoidance, behavior, temperature, fish, responses

Annual and lunar breeding rhythmicity in females of the terrestrial hermit crab Coenobita rugosus H. Milne Edwards, 1837 (Decapoda: Anomura: Coenobitidae) in Okinawa, Japan

2019 ◽  
Vol 39 (4) ◽  
pp. 493-499
Author(s):  
Naoya Osaka ◽  
Akihiro Takemura
Keyword(s):  
Hermit Crab ◽  
Ovarian Development ◽  
Full Moon ◽  
Gonadosomatic Index ◽  
Larval Release ◽  
Temperature Group ◽  
Proximate Factor ◽  
Two Temperatures ◽  
Monthly Changes ◽  
New Moon

Abstract We investigated the reproductive characteristics of a terrestrial hermit crab (Coenobita rugosus H. Milne Edwards, 1837) inhabiting Okinawa-Jima. Monthly changes in the gonadosomatic index and ovarian histology revealed that this species had fully developed oocytes from May to October. Data showing that females with (ovigerous females) and without (non-ovigerous females) embryos on their pleopods appeared simultaneously on the shore from June to September 2014 demonstrates that this species undergoes larval release several times for four months. When non-ovigerous females were reared under a combination of two day lengths and two temperatures, oocyte development was induced in the high-temperature group, suggesting that temperature is a proximate factor in ovarian development. The weekly collection of females during the spawning season revealed that the proportion of fully developed oocytes in an ovary increased toward the time of the new moon and decreased around the first-quarter moon, suggesting that this species is a lunar-spawner with a new-moon preference. Some females releasing larvae around the new or full moon were recaptured at approximately 30 d intervals, suggesting at least two major groups with lunar-synchronized larval release. The ovarian development and larval release of C. rugosus are likely entrained to external factors, which change periodically in their habitats.

Impact of puma predation on the decline and recovery of a mule deer population in southeastern Idaho

2006 ◽  
Vol 84 (11) ◽  
pp. 1555-1565 ◽  
Author(s):  
J.W. Laundré ◽  
L. Hernández ◽  
S.G. Clark
Keyword(s):  
Population Change ◽  
Puma Concolor ◽  
Mule Deer ◽  
Odocoileus Hemionus ◽  
Winter Mortality ◽  
Deer Population ◽  
Before And After ◽  
Proximate Factor ◽  
A Minor ◽  
The Impact

We modeled the impact of puma ( Puma concolor (L., 1771)) predation on the decline and recovery of mule deer ( Odocoileus hemionus (Rafinesque, 1817)) in southern Idaho based on estimates of puma numbers, predation rates of pumas, and reproductive variables of deer. Deer populations peaked in 1992–1993, then declined more than 55% and remained low for the next 11 years. Puma numbers peaked 4–6 years after deer populations peaked but then declined to original levels. Estimated puma predation on the deer population before and after the decline was 2.2%–3.3% and 3.1%–5.8%, respectively. At high puma densities (>3 pumas/100 km2), predation by pumas delayed deer recovery by 2–3 years. Percent winter mortality of fawns (r2 = 0.62, P < 0.001) and adult female deer (r2 = 0.68, P < 0.001) correlated positively with December–January snowfall. Incorporation of winter snowfall amounts in the model produced a pattern of deer population change matching estimated changes based on field survey data. We conclude that pumas probably were a minor factor in the decline of the deer population in our area and did not suppress deer recovery. We propose that winter snowfall was the primary ultimate and proximate factor in the deer decline and suppression of their recovery.

Parental effort of American kestrels: the role of variation in brood size

2003 ◽  
Vol 81 (5) ◽  
pp. 852-860 ◽  
Author(s):  
Russell D Dawson ◽  
Gary R Bortolotti
Keyword(s):  
Brood Size ◽  
Size Variation ◽  
Parental Effort ◽  
Proximate Determinant ◽  
American Kestrels ◽  
Experimental Variation ◽  
Proximate Determinants ◽  
Proximate Factor ◽  
And Control

Brood size has the potential to determine the allocation of resources between parents and offspring, as well as influence the relative contributions of each sex to parental effort. However, it is unclear whether brood size is the proximate determinant of parental effort, or conversely whether parental effort is the proximate factor to which brood size is adjusted. If brood size determines parental effort, then theory suggests that parental effort should vary with experimental changes in brood size. In contrast, if parental effort determines brood size, then parental effort is expected to be independent of experimental variation in brood size. To distinguish between these hypotheses, we experimentally reduced brood sizes of American kestrels (Falco sparverius). Our results suggest that male parents responded to brood-size variation and adjusted their provisioning behaviour accordingly. Conversely, female parents did not adjust provisioning in response to brood size, and as a result, offspring in reduced broods received more food on a per-nestling basis. However, condition and survival of offspring were similar in reduced broods and control young, which may have been the result of larger food requirements of small broods, owing to increased thermoregulatory costs compared with control broods. Female parents with reduced broods also did not brood offspring more often, further suggesting that females do not respond to variation in brood size. We conclude that the proximate determinants of parental effort are sex-specific in American kestrels: for males, brood size determines behaviour, whereas for females, behaviour may be a proximate factor determining brood size.

Preferred Temperature of Two Sympatric Ambystoma Larvae: A Proximate Factor in Niche Segregation?

Copeia ◽  
1983 ◽  
Vol 1983 (4) ◽  
pp. 1001 ◽  
Author(s):  
Jay R. Stauffer ◽  
J. Edward Gates ◽  
William L. Goodfellow
Keyword(s):  
Niche Segregation ◽  
Preferred Temperature ◽  
Proximate Factor

Soil-Eating by Red Leaf Monkeys (Presbytis rubicunda) in Sabah, Northern Borneo

Biotropica ◽  
1988 ◽  
Vol 20 (3) ◽  
pp. 252 ◽  
Author(s):  
A. G. Davies ◽  
I. C. Baillie
Keyword(s):  
Soil Eating ◽  
Presbytis Rubicunda ◽  
Leaf Monkeys

Navigating the Path of Least Resistance: Financial Deregulation and the Origins of the Japanese Crisis

2005 ◽  
Vol 5 (3) ◽  
pp. 427-464 ◽  
Author(s):  
Yves Tiberghien
Keyword(s):  
United States ◽  
Political Economy ◽  
Interest Groups ◽  
The United States ◽  
Political Resistance ◽  
Political Leaders ◽  
Financial Deregulation ◽  
Proximate Factor ◽  
The Government ◽  
Made In

This article reexamines the period of the Japanese bubble (1985–1990) and emphasizes ill-supervised and ill-sequenced financial deregulation as a key proximate factor. Given the subsequent costs of this political choice, what explains such a path of domestic financial deregulation without the establishment of corresponding supervisory institutions? I argue that the suboptimal Japanese outcome represents the equilibrium point for political leaders who had to balance global pressures to deregulate the economy, corporate pressures to liberalize finance, and domestic resistance by an array of politically connected interest groups. The government chose ill-supervised financial deregulation as the path of least political resistance and the golden bullet that could both defuse trade tensions with the United States and readjust the Japanese political economy in a harmless way. Instead, as they interacted with other factors, the choices made in the early 1980s destabilized the Japanese system and carried the seeds of the ensuing financial crisis.

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