Marsilea mutica (Marsileaceae) newly reported in Texas, U.S.A.

Natural variation in neuroendocrine traits is poorly understood, despite the importance of variation in brain function and evolution. Most rodents in the temperate zones inhibit reproduction and other nonessential functions in short winter photoperiods, but some have little or no reproductive response. We tested whether genetic variability in reproductive seasonality is related to individual differences in the neuronal function of the gonadotropin-releasing hormone network, as assessed by the number and location of mature gonadotropin-releasing hormone-secreting neurons under inhibitory and excitatory photoperiods. The experiments used lines of Peromyscus leucopus previously developed by selection from a wild population. One line contained individuals reproductively inhibited by short photoperiod, and the other line contained individuals nonresponsive to short photoperiod. Expression of mature gonadotropin-releasing hormone (GnRH) immunoreactivity in the brain was detected using SMI-41 antibody in the single-labeled avidin-biotin-peroxidase-complex method. Nonresponsive mice had 50% more immunoreactive GnRH neurons than reproductively inhibited mice in both short- and long-day photoperiods. The greatest differences were in the anterior hypothalamus and preoptic areas. In contrast, we detected no significant within-lines differences in the number or location of immunoreactive GnRH neurons between photoperiod treatments. Our data indicate that high levels of genetic variation in a single wild population for a specific neuronal trait are related to phenotypic variation in a life history trait, i.e., winter reproduction. Variation in GnRH neuronal activity may underlie some of the natural reproductive and life history variation observed in wild populations of P. leucopus. Similar genetic variation in neuronal traits may be present in humans and other species.

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First record of the exotic species Axis axis (Erxleben, 1777) (Artiodactyla, Cervidae) in the state of Santa Catarina, southern Brazil

Check List ◽

10.15560/16.5.1139 ◽

2020 ◽

Vol 16 (5) ◽

pp. 1139-1142

Author(s):

Jackson F. Preuss ◽

Eduarda Posser ◽

Laura B. Albrecht ◽

Victor P.R. da Silva ◽

Fernanda C. Bandiera

Keyword(s):

Exotic Species ◽

Local Community ◽

First Record ◽

The State ◽

Natural Environments ◽

Southern Brazil ◽

Santa Catarina ◽

Negative Factor ◽

Axis Axis ◽

First Occurrence

In this work, we describe the first occurrence record of the exotic species of deer Axis axis (Erxleben, 1777) from natural environments of the state of Santa Catarina, southern Brazil. The study provides information about the implications of the invasion of the region’s ecosystem, which is seen as a negative factor in the local community and represents a major conservation challenge.

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Gene Expression Life History Markers in a Hatchery and a Wild Population of Young-of-the-Year Oncorhynchus mykiss

10.15760/etd.1444 ◽

2000 ◽

Author(s):

Ian Garrett

Keyword(s):

Gene Expression ◽

Life History ◽

Oncorhynchus Mykiss ◽

Wild Population ◽

Young Of The Year

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Some aspects of the biology of the North American ostracod <i>Sarsiella zostericola</i> Cushman in the vicinity of a British power station

Journal of Micropalaeontology ◽

10.1144/jm.6.1.57 ◽

1987 ◽

Vol 6 (1) ◽

pp. 57-62 ◽

Cited By ~ 6

Author(s):

R. N. Bamber

Keyword(s):

Life History ◽

Sex Ratio ◽

Exotic Species ◽

North American ◽

Water Discharge ◽

Cooling Water ◽

Power Station ◽

The North ◽

Discharge Canal ◽

Thermally Stressed

Abstract. A population of the North American myodocopid ostracod Sarseilla zostericola Cushman has become established in the River Medway, Kent, in the vicinity of the cooling water discharge from Kingsnorth Power Station, though not living in the thermally stressed regions of the discharge environment. The species is assumed to have been introduced with North American oysters, but is not an example of an ‘exotic’ species surviving in association with the heated discharge. The Kingsnorth individuals are larger and more fecund than those of studied North American populations. The breeding biology, life history and sex ratio are discussed. It is suggested that the intolerance of S. zostericola to the conditions of the thermally stressed discharge canal is associated with shell physiology.

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Grinnelian and Eltonian niche conservatism of the European honeybee (Apis mellifera) in its exotic distribution

Sociobiology ◽

10.13102/sociobiology.v67i2.4901 ◽

2020 ◽

Vol 67 (2) ◽

pp. 239

Author(s):

Anderson Matos Medina ◽

Mário Almeida-Neto

Keyword(s):

Life History ◽

Apis Mellifera ◽

Exotic Species ◽

Resource Use ◽

Life History Traits ◽

Niche Conservatism ◽

Species Invasion ◽

Species Invasions ◽

History Of ◽

European Honeybee

The understanding of how niche-related traits change during species invasion have prompted what is now known as the niche conservatism principle. Most studies that have tested the niche conservatism principle have focused on the extent to which the species’ climatic niches remain stable in their exotic distribution. However, it is equality important to address how biotic specialization, i.e. resource use, changes during exotic species invasions. Here, we use the widespread European honeybee (Apis mellifera) to understand whether its Grinnelian and Eltonian niches changed in its exotic distribution using tests of abiotic and biotic niche conservatism. We found that both niche domains of the European honeybee remained stable in its exotic distribution, which means that neither the climatic niche nor the biotic specialization showed significant differences between the native and the exotic ranges. Our findings that climatic and resource use are coupled can be explained by A. mellifera’s long history of domestication and the possibility that life history traits (e.g., polyandry) may have shaped this species’ large niche over the course of evolution and therefore facilitated exotic ranges colonization.

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Parent age, lifespan and offspring survival: structured variation in life history in a wild population

Journal of Animal Ecology ◽

10.1111/j.1365-2656.2010.01669.x ◽

2010 ◽

Cited By ~ 4

Author(s):

Jane M. Reid ◽

Eric M. Bignal ◽

Sue Bignal ◽

Davy I. McCracken ◽

Maria I. Bogdanova ◽

...

Keyword(s):

Life History ◽

Wild Population ◽

Offspring Survival

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Life history correlates of fecal bacterial species richness in a wild population of the blue titCyanistes caeruleus

Ecology and Evolution ◽

10.1002/ece3.1384 ◽

2015 ◽

Vol 5 (4) ◽

pp. 821-835 ◽

Cited By ~ 17

Author(s):

Clare McW. H. Benskin ◽

Glenn Rhodes ◽

Roger W. Pickup ◽

Mark C. Mainwaring ◽

Kenneth Wilson ◽

...

Keyword(s):

Life History ◽

Species Richness ◽

Wild Population ◽

Bacterial Species

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Dispersal as a source of variation in age-specific reproductive strategies in a wild population of lizards

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2015.1741 ◽

2015 ◽

Vol 282 (1820) ◽

pp. 20151741 ◽

Cited By ~ 3

Author(s):

Olivier Cotto ◽

Manuel Massot ◽

Ophélie Ronce ◽

Jean Clobert

Keyword(s):

Life History ◽

Body Condition ◽

Life History Traits ◽

Reproductive Effort ◽

Wild Population ◽

Recent Theory ◽

Offspring Sex Ratio ◽

Dispersal Syndromes ◽

Common Lizard ◽

High Investment

Dispersal syndromes describe the patterns of covariation of morphological, behavioural, and life-history traits associated with dispersal. Studying dispersal syndromes is critical to understanding the demographic and genetic consequences of movements. Among studies describing the association of life-history traits with dispersal, there is anecdotal evidence suggesting that dispersal syndromes can vary with age. Recent theory also suggests that dispersive and philopatric individuals might have different age-specific reproductive efforts. In a wild population of the common lizard ( Zootoca vivipara ), we investigated whether dispersive and philopatric individuals have different age-specific reproductive effort, survival, offspring body condition, and offspring sex ratio. Consistent with theoretical predictions, we found that young dispersive females have a higher reproductive effort than young philopatric females. Our results also suggest that the early high investment in reproduction of dispersive females trades-off with an earlier onset of senescence than in philopatric females. We further found that young dispersive females produce smaller offspring in lower body condition than do young philopatric females. Overall, our results provide empirical evidence that dispersive and philopatric individuals have different age-specific life-history traits.

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Variation in levels of luteinizing hormone and reproductive photoresponsiveness in a population of white-footed mice (Peromyscus leucopus)

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00686.2009 ◽

2010 ◽

Vol 298 (6) ◽

pp. R1543-R1548 ◽

Cited By ~ 8

Author(s):

Paul D. Heideman ◽

Julian T. Pittman ◽

Kristin A. Schubert ◽

Christen M. R. Dubois ◽

Jennifer Bowles ◽

...

Keyword(s):

Genetic Variation ◽

Life History ◽

Luteinizing Hormone ◽

Artificial Selection ◽

Wild Population ◽

Peromyscus Leucopus ◽

Life History Strategies ◽

Life History Trait ◽

Selection Line ◽

In The Wild

Natural genetic variation in reproduction and life history strategies is a manifestation of variation in underlying regulatory neuronal and endocrine systems. A test of the hypothesis that genetic variation in luteinizing hormone (LH) level could be related to a life history trait, seasonal reproduction, was conducted on artificial selection lines from a wild-source population of white-footed mice ( Peromyscus leucopus ). Variation exists in the degree of suppression of reproduction by winter short-day photoperiods (SD) in wild-source individuals and in the laboratory population. In this population, most individuals from a photoperiod-responsive (R) artificial selection line are strongly suppressed reproductively in SD, while most individuals from a photoperiod-nonresponsive (NR) artificial selection line are only weakly reproductively suppressed in SD. We assayed levels of LH to test for genetic variation between lines that could contribute to variation in reproductive status in SD. Females from both lines were raised in long-day photoperiods (LD) or SD, ovariectomized under isoflurane anesthesia, and given estradiol implants. Levels of LH were significantly higher in the NR line than in the R line, indicating genetic variation for levels of LH. Levels of LH were higher in LD than in SD, indicating that levels of LH were sensitive to photoperiod treatment even with a controlled level of estradiol negative feedback. The results indicate that there is genetic variation in levels of LH that could be functionally important both in the laboratory in SD and in the wild population in winter. Thus genetic variation in levels of LH is a plausible causal factor determining winter reproductive phenotype in the wild population.

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