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1. The Menstrual Cycle of the Primates.—Part VI. Further Observations on the Breeding of Primates, with special reference to the Suborders Lemuroidea and Tarsioidea

Author:
S. Zuckerman
Source:
Proceedings of the Zoological Society of London 1932 v.102 no.4 pp. 1059-1075
ISSN:
0370-2774
Subject:
Lemur; Nycticebus; Papio hamadryas; Tupaia; animals; birth rate; breeding; breeding season; menstrual cycle; seasonal variation
Abstract:
... 1 The Common Macaque (31. irus) experiences a conspicuous seasonal variation in fertility. 2 The Hamadryas baboon (P. hamadryas) breeds continuously, but also experiences a seasonal variation in its birth‐rate. The period in which it reaches its maximum of fertility is different from that of the Common Macaque. 3 The Spectral Tarsier (Tarsius spectrum) breeds throughout the year, and apparently wi ...
DOI:
10.1111/j.1096-3642.1932.tb01576.x

2. Parameters for Seasonally Breeding Populations

Author:
Graeme Caughley
Source:
Ecology 1967 v.48 no.5 pp. 834-839
ISSN:
0012-9658
Subject:
birth rate; breeding; equations; mortality; sheep; statistics
Abstract:
... Lotka's equations relating the parameters of populations with no seasonal trend in birth rates and Fisher's formula for "reproductive value" are modified to describe populations with restricted annual seasons of birth. The parameters "net reproductive rate" and "mean generation length" provide statistics and dubious utility for populations with overlapping generations. New definitions of birth rat ...
DOI:
10.2307/1933741

3. The Intrinsic Rate of Natural Increase of Irradiated Peromyscus in the Laboratory

Author:
Norman R. French; Howard W. Kaaz
Source:
Ecology 1968 v.49 no.6 pp. 1172-1179
ISSN:
0012-9658
Subject:
Peromyscus maniculatus; adults; birth rate; conception; females; gamma radiation; irradiation; longevity; males; mortality; progeny; reproductive performance; small mammals
Abstract:
... This study was undertaken to determine the effect of continuous low—level exposure to gamma radiation on a population of small mammals (Peromyscus maniculatus sonoriensis) in the laboratory. The average dose rate was slightly greater than 1 roentgen/day. One group was exposed as adults, with irradiation beginning when they were weaned (age 3 to 4 weeks); another group was the offspring of the irra ...
DOI:
10.2307/1934507

4. The Distribution and Dispersal of Pikas: Consequences of Insular Population Structure

Author:
Andrew T. Smith
Source:
Ecology 1974 v.55 no.5 pp. 1112-1119
ISSN:
0012-9658
Subject:
Ochotona; adults; birth rate; extinction; habitats; islands; juveniles; mammals; mortality; population structure; probability; Sierra Nevada (California)
Abstract:
... The population structure of a small boreal mammal, the pika (Ochotona princeps), was analyzed from demographic data and the observed spacing of populations on discrete islands of habitat in the Sierra Nevada of California. These islands of habitat varied in size and distance from one another. Not all of the islands were occupied and most seemed to contain fewer individuals than they could hold. Th ...
DOI:
10.2307/1940361

5. A Population Study of Irradiated Desert Rodents

Author:
N. R. French; B. G. Maza; H. O. Hill; A. P. Aschwanden; H. W. Kaaz
Source:
Ecological monographs 1974 v.44 no.1 pp. 45-72
ISSN:
0012-9615
Subject:
Perognathus; annuals; birth rate; censuses; death; diet; food availability; foods; growing season; histology; irradiation; longevity; plants (botany); pollution; reproduction; rodents; seeds; vegetative growth
Abstract:
... An experiment was begun in 1963 to evaluate effects of long—term low—level radiation exposure on desert populations of plants and animals. Monthly censuses of four species of heteromyid rodents in three 9—ha enclosures and one non—enclosed area indicate great year—to—year changes in densities of the nonirradiated populations and even greater fluctuations in the irradiated populations. Although mag ...
DOI:
10.2307/1942318

6. Factors Regulating the Distribution and Population Dynamics of the Amphipod Gammarus palustris in an Intertidal Salt Marsh Community

Author:
Robert F. Van Dolah
Source:
Ecological monographs 1978 v.48 no.2 pp. 191-217
ISSN:
0012-9615
Subject:
Fundulus heteroclitus; Gammarus; Spartina; adults; autumn; birth rate; cold stress; culms; environmental factors; estuaries; fauna; females; heat; interspecific competition; intraspecific competition; juveniles; littoral zone; mortality; population dynamics; predation; rivers; salt marshes; seasonal variation; spring; summer; winter; Chesapeake Bay
Abstract:
... Seasonal changes in the intertidal distribution, abundance and population dynamics of the epifaunal amphipod Gammarus palustris were studied in salt marshes bordering 2 estuarine rivers flowing into the Chesapeake Bay. The amphipod populations inhabiting the Patuxent River study site showed abundance peaks during the spring and autumn, and major declines in density during the summer and winter. Po ...
DOI:
10.2307/2937299

7. Intertidal Landscapes: Disturbance and the Dynamics of Pattern

Author:
R. T. Paine; Simon A. Levin
Source:
Ecological monographs 1981 v.51 no.2 pp. 145-178
ISSN:
0012-9615
Subject:
Balanus; Mytilus californianus; birth rate; breeding season; coasts; death; growth curves; landscapes; larvae; littoral zone; models; mussels; plankton; prediction; seasonal variation; species richness; summer; winter; Washington (state)
Abstract:
... The mussel Mytilus californianus is a competitive dominant on wave—swept rocky intertidal shores. Mussel beds may exist as extensive monocultures; more often they are an everchanging mosaic of many species which inhabit wave—generated patches or gaps. This paper describes observations and experiments designed to measure the critical parameters of a model of patch birth and death, and to use the mo ...
DOI:
10.2307/2937261

8. Responses in Growth Mortality, and Reproduction to Variable Food Levels by the Rotifer, Asplanchna Girodi

Author:
J. Roy Robertson; George W. Salt
Source:
Ecology 1981 v.62 no.6 pp. 1585-1596
ISSN:
0012-9658
Subject:
Paramecium tetraurelia; Rotifera; adults; birth rate; fecundity; food intake; longevity; mortality; population density; progeny; starvation
Abstract:
... We have determined the changes in fecundity, mortality, and growth of the ploimate rotifer, Asplanchna girodi, in response to variations in food density. Rotifers were raised from birth on either fixed allotments of Paramecium tetraurelia or on allotments that varied temporally. Fecundity, growth rates, and size of the rotifer at the time of birth of the first offspring varied directly with food l ...
DOI:
10.2307/1941514

9. How Well Does the Edmonson‐Paloheimo Model Approximate Instantaneous Birth Rates?

Author:
Michael Lynch
Source:
Ecology 1982 v.63 no.1 pp. 12-18
ISSN:
0012-9658
Subject:
Daphnia pulex; age structure; analysis of variance; birth rate; eggs; equations; factor analysis; models; mortality; seasonal variation; variance; zooplankton
Abstract:
... An equation independently derived by Edmondson and Paloheimo for estimating instantaneous birth rates without a knowledge of mortality rates has been extensively employed by zooplankton ecologists. This expression is exactly true only under the unlikely conditions that the age distribution is stable and that egg mortality is equal to that averaged across the entire population. Here I compare estim ...
DOI:
10.2307/1937025

10. Seasonal Succession in a Natural Daphnia Assemblage

Author:
William R. DeMott
Source:
Ecological monographs 1983 v.53 no.3 pp. 321-340
ISSN:
0012-9615
Subject:
Chlamydomonas; Daphnia longispina; algae; autumn; birth rate; digestive system; eggs; field experimentation; fish; grazing trials; intraspecific competition; lakes; males; mortality; parthenogenesis; phytoplankton; population growth; population structure; predation; reproductive success; spring; summer; Vermont
Abstract:
... This study uses descriptive data and field experiments to examine a seasonal succession between two planktonic grazers (Daphnia rosea and Daphnia pulicaria) in a small Vermont lake. Each year Daphnia populations hatched from resting eggs during May and both species produced numerous parthenogenetic generations before the appearance of males and ephippia in late September. During the 2 yr of study, ...
DOI:
10.2307/1942534

11. Egg Development of a Chydorid Cladoceran, Chydorus Sphaericus, Exposed to Constant and Alternating Tempeatures: Significance to Secondary Productivity in Fresh Waters

Author:
Dewey G. Meyers
Source:
Ecology 1984 v.65 no.1 pp. 309-320
ISSN:
0012-9658
Subject:
Cladocera; acclimation; animals; birth rate; eggs; embryogenesis; field experimentation; hatching; littoral zone; oviposition; prediction; secondary productivity; water temperature
Abstract:
... Eggs of the chydorid cladoceran, chydorus sphaericus, were exposed to five constant temperatures of 10°, 15°, 20°, 25°, and 30°, and three 12.12 h diel thermal cycles of 10°:20° (daily mean [x] of 15°), 15°:25°, (° = 20°), and 20°:30° (x = 25°). Diurnal temperature fluctuations decreased the duration of development and, consequently, accelerated the developmental rate an average of 10% over the co ...
DOI:
10.2307/1939483

12. Comparative Ecology of Blue Monkeys (Cercopithecus Mitis) in High‐ and Low‐Density Subpopulations

Author:
Thomas M. Butynski
Source:
Ecological monographs 1990 v.60 no.1 pp. 1-26
ISSN:
0012-9615
Subject:
Cercopithecus mitis; adults; birth rate; carrying capacity; comparative study; demographic statistics; diet; females; food production; foods; foraging; forests; fruits; habitats; home range; hybridization; interspecific competition; males; monkeys; population density; population growth; reproductive success; species richness; trees; Uganda
Abstract:
... Two subpopulations of blue monkeys (Cercopithecus mitis), located 10 km apart, were studied in Kibale Forest, Uganda, for most of a 6—yr period (1978—1984). This study was undertaken (1) to assess and evaluate the major differences in the environment and in the behavioral ecology of blue monkeys living at high and low densities and (2) to explain the differences in blue monkey densities in the two ...
DOI:
10.2307/1943024

13. The role of neighborhood competition in the spacing and diversity of ant communities

Author:
Ryti, R.T.; Case, T.J.
Source:
American naturalist 1992 v.139 no.2 pp. 355-374
ISSN:
0003-0147
Subject:
Formicidae; insect communities; ecological competition; spatial distribution; birth rate; mortality; adults; simulation models; juveniles
DOI:
10.1086/285331

14. Birth outcomes to rural Illinois residents: is there a crisis?

Author:
Rock, S.M.; Straub, L.A.
Source:
Journal of rural health 1994 v.10 no.2 pp. 122-130
ISSN:
0890-765X
Subject:
health services; rural areas; supply; infants; parturition; birth rate; Illinois
Abstract:
... In recent years, the supply of obstetric services in rural areas has been a concern. At the same time, the demand for such services has been affected by the reduction in population and economic base. This article explores the extent of these trends in Illinois and whether they have led to a deterioration in amount of prenatal care and birth outcomes. Using birth certificate and infant death data f ...
DOI:
10.1111/j.1748-0361.1994.tb00219.x
PubMed:
10134713

15. Economic effects of the outmigration of obstetric services in a rural county

Author:
Thompson, J.G.
Source:
Journal of rural health 1996 v.12 no.2 pp. 100-109
ISSN:
0890-765X
Subject:
health services; rural communities; case studies; economic impact; rural population; birth rate; Wyoming
Abstract:
... Obstetrical health care resources have been declining in rural areas since 1980, resulting in reduced prenatal care that can result in higher medical costs. Loss of health care services is known to have negative economic consequences for rural communities. This article illustrates how hospitals and other providers of medical services can be used as vehicles for local economic development. Provisio ...
DOI:
10.1111/j.1748-0361.1996.tb00781.x
PubMed:
10159188

16. Stochastic model of spatial spread and control of tsetse flies (Diptera: Muscidae)

Author:
Yu, P.; Habtemariam, T.; Oryang, D.; Obasa, M.; Nganwa, D.; Robnett, V.
Source:
Environmental entomology 1996 v.25 no.1 pp. 78-84
ISSN:
0046-225X
Subject:
Glossina; spatial distribution; birth rate; mortality; trypanosomiasis; disease prevention; insect control; disease vectors; stochastic processes; vector control; population
Abstract:
... A stochastic model is developed to study the spatial spread and control of tsetse flies, Glossina spp. In this model, the movement mechanism is described by the travel direction and distance of an individual tsetse fly, birth and death rates are described by probability distributions, and some control measures are considered. The model is used to estimate the straight-line distance traveled in the ...
DOI:
10.1093/ee/25.1.78

17. Human sociogeophysics — Phase I: Explaining the macroscopic patterns of man on earth

Author:
A. Iberall; D. Wilkinson
Source:
GeoJournal 1997 v.8 no.2 pp. 171-179
ISSN:
0343-2521
Subject:
birth rate; breeding; demography; humans; mortality; people; physical models; physics; walking
Abstract:
... The demography of man on earth is treated by a physical model for that forward transport for the subspecies in time. By examining the distribution of man and his Neanderthaler precursor, it is inferred, as a likely hypothesis, that the initial “Phase I” expansion of man on earth (40,000–15,000 ybp) was at a constant density of about 0.04 persons per sq.km with little or no remixing. We suggest tha ...
DOI:
10.1007/BF00231495

18. Impact of health service provision on mothers and infants in a rural village in North West Frontier Province, Pakistan

Author:
Northrop-Clewes, C.A.; Ahmad, N.; Paracha, P.I.; Thurnham, D.I.
Source:
Public health nutrition 1998 v.1 no.1 pp. 51-59
ISSN:
1368-9800
Subject:
water supply; literacy; mothers; body weight; sanitation; vaccination; socioeconomic status; rural areas; length; birth rate; infants; mortality; health services; Pakistan
PubMed:
10555531

19. On the scaling of habitat specificity with body size

Author:
Yaron Ziv
Source:
Ecology 2000 v.81 no.10 pp. 2932-2938
ISSN:
0012-9658
Subject:
allometry; birth rate; body size; carrying capacity; energy; equations; habitats; landscapes; mammals; metabolism; mortality; population growth; simulation models
Abstract:
... Larger species tend to occupy more habitats, but a theoretical framework for the pattern is lacking. I modified the continuous‐time logistic equation of population growth in two ways to allow for such a habitat‐based theoretical framework. First, I separated birth rate from death rate. Second, I included two new terms in the equation: (1) an explicit spatial variable for habitat quality that refle ...
DOI:
10.1890/0012-9658(2000)081[2932:OTSOHS]2.0.CO;2

20. The state of nutrition in Saudi Arabia

Author:
Madani, K.A.; Al-Amoudi, N.S.; Kumosani, T.A.
Source:
Nutrition and health 2000 v.14 no.1 pp. 17-31
ISSN:
0260-1060
Subject:
malnutrition; food groups; population growth; obesity; birth rate; nutrient intake; eating habits; women; neoplasms; heart diseases; sex ratio; population density; incidence; food consumption; blood lipids; men; nutrient deficiencies; diabetes; foodways; diet; nutritional status; cholesterol; population; Saudi Arabia
DOI:
10.1177/026010600001400103
PubMed:
10840810