Asian elephants exhibit post-reproductive lifespans

Abstract Background The existence of extended post-reproductive lifespan is an evolutionary puzzle, and its taxonomic prevalence is debated. One way of measuring post-reproductive life is with post-reproductive representation, the proportion of adult years lived by females after cessation of reproduction. Analyses of post-reproductive representation in mammals have claimed that only humans and some toothed whale species exhibit extended post-reproductive life, but there are suggestions of a post-reproductive stage for false killer whales and Asian elephants. Here, we investigate the presence of post-reproductive lifespan in Asian elephants using an extended demographic dataset collected from semi-captive timber elephants in Myanmar. Furthermore, we investigate the sensitivity of post-reproductive representation values to availability of long-term data over 50 years. Results We find support for the presence of an extended post-reproductive stage in Asian elephants, and that post-reproductive representation and its underlying demographic rates depend on the length of study period in a long-lived animal. Conclusions The extended post-reproductive lifespan is unlikely due to physiological reproductive cessation, and may instead be driven by mating preferences or condition-dependent fertility. Our results also show that it is crucial to revisit such population measures in long-lived species as more data is collected, and if the typical lifespan of the species exceeds the initial study period.

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Mapped quadrats in sagebrush steppe: long-term data for analyzing demographic rates and plant–plant interactions

Ecology ◽

10.1890/10-0404.1 ◽

2010 ◽

Vol 91 (11) ◽

pp. 3427-3427 ◽

Cited By ~ 24

Author(s):

Luke Zachmann ◽

Corey Moffet ◽

Peter Adler

Keyword(s):

Sagebrush Steppe ◽

Plant Interactions ◽

Demographic Rates ◽

Term Data ◽

Plant Plant

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Musth and its effects on male–male and male–female associations in Asian elephants

Journal of Mammalogy ◽

10.1093/jmammal/gyz190 ◽

2019 ◽

Vol 101 (1) ◽

pp. 259-270 ◽

Cited By ~ 1

Author(s):

P Keerthipriya ◽

S Nandini ◽

Hansraj Gautam ◽

T Revathe ◽

T N C Vidya

Keyword(s):

Southern India ◽

Adult Males ◽

Age Classes ◽

Asian Elephants ◽

Young Males ◽

Gain Access ◽

Older Males ◽

Term Data

Abstract Musth is an annual, asynchronous, rut-like phenomenon observed in male elephants. We examined whether musth is a roving strategy, and whether musth provides a temporary advantage to young males through increased access to female groups. We collected long-term data on the musth status, associations, and locations of male elephants in the Kabini population in southern India. We sighted older males more frequently in musth than younger males. We found a greater turnover of musth than non-musth males in the study area, suggesting that musth is a roving strategy, enabling males to travel widely and away from their non-musth range. Contrary to our expectation, young (15–30 years old) males spent a smaller proportion of their musth time than their non-musth time associating with females, and associated with similarly sized female groups irrespective of musth status. Old (> 30 years old) males spent only a slightly higher proportion of their musth time than non-musth time with female groups, but associated with larger female groups during musth. Although old males in musth associated with young non-musth males more often in the presence, than in the absence, of females, young males in musth were never sighted with old non-musth males in the presence of females. Therefore, the payoff from musth, as a strategy to gain access to females, was age-specific; musth in old males allowed for increased association with females, while musth in young males restricted their access to females. There was no spatial avoidance between musth and non-musth adult males at scales larger than immediate associations. Our results suggest that musth seems to be primarily a roving strategy for old males to find and associate with females and not a strategy for young males to gain a temporary advantage over old males, within the broad age-classes that we examined.

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Hydrogeological responses in tropical mountainous springs

Memorias del I Congreso Internacional de Ciencias Exactas y Naturales ◽

10.15359/cicen.1.37 ◽

2019 ◽

Author(s):

Ricardo Sánchez-Murillo

Keyword(s):

Costa Rica ◽

Isotope Composition ◽

Central Valley ◽

Distribution Functions ◽

Geochemical Composition ◽

Transit Times ◽

Management Plans ◽

Best Fit ◽

Term Data

This study presents a hydrogeochemical analysis of spring responses (2013-2017) in the tropical mountainous region of the Central Valley of Costa Rica. The isotopic distribution of δ18O and δ2H in rainfall resulted in a highly significant meteoric water line: δ2H = 7.93×δ18O + 10.37 (r2=0.97). Rainfall isotope composition exhibited a strong dependent seasonality. The isotopic variation (δ18O) of two springs within the Barva aquifer was simulated using the FlowPC program to determine mean transit times (MTTs). Exponential-piston and dispersion distribution functions provided the best-fit to the observed isotopic composition at Flores and Sacramento springs, respectively. MTTs corresponded to 1.23±0.03 (Sacramento) and 1.42±0.04 (Flores) years. The greater MTT was represented by a homogeneous geochemical composition at Flores, whereas the smaller MTT at Sacramento is reflected in a more variable geochemical response. The results may be used to enhance modelling efforts in central Costa Rica, whereby scarcity of long-term data limits water resources management plans.

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Morphometric studies of artemia males from different populations of the Altai region

Rybovodstvo i rybnoe hozjajstvo (Fish Breeding and Fisheries) ◽

10.33920/sel-09-2007-03 ◽

2020 ◽

pp. 28-38

Author(s):

L. Vesnina ◽

G. Lukerina ◽

T. Ronzhina ◽

A. Savos’kin ◽

D. Surkov

Keyword(s):

Sexual Dimorphism ◽

Hydrogen Index ◽

Morphometric Parameters ◽

Altai Region ◽

Sexual Structure ◽

Different Populations ◽

Artemia Population ◽

Term Data ◽

Brine Salinity

The long-term data from morphometric studies of Artemia males from bisexual and parthenogenetic populations from hyperhaline reservoirs of the Altai region (Bolshoe Yarovoe Lake, Maloe Shklo Lake, and the Tanatar Lakes system) is analyzed in this paper. The description of signs of sexual dimorphism and sexual structure in different populations is given. The influence of brine salinity and hydrogen index on morphometric parameters of males was analyzed. There are differences in the sexual structure of the Artemia population: in the lakes Maloe Shklo and the thanatar system, the populations are bisexual (the share of males is 28.5 — 75.0 %), in the lake Bolshoe yarovoe — parthenogenetic (the share of males on average does not exceed 3 %). At the same time, sexual dimorphism is typical for both types of populations: females are larger than males, males have a larger head (the distance between the eyes is greater by 15.5 %, the diameter of the eye is 26.1 %, the length of the antenna is 22.3 %) and a larger number of bristles (36.1 %). The greatest variability is observed in the parameters of the Furka structure associated with the salinity of water by feedback and the pH — line indicator. Significant differences between the samples of males were revealed. The largest number of significant differences in morphometric indicators was found between samples of males from bisexual populations (lake thanatar and lake Maloe Shklo), the smallest — between males from the parthenogenetic population of lake Bolshoe yarovoe and males from lake Maloe Shklo.

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Information technology. Digitally recorded media for information interchange and storage. Test method for the estimation of lifetime of optical disks for long-term data storage

10.3403/30341531u ◽

2017 ◽

Keyword(s):

Information Technology ◽

Data Storage ◽

Test Method ◽

Storage Test ◽

Optical Disks ◽

Information Interchange ◽

And Storage ◽

Term Data

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Information technology. Digitally recorded media for information interchange and storage. Test method for the estimation of lifetime of optical disks for long-term data storage

10.3403/30341531 ◽

2017 ◽

Keyword(s):

Information Technology ◽

Data Storage ◽

Test Method ◽

Storage Test ◽

Optical Disks ◽

Information Interchange ◽

And Storage ◽

Term Data

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Diel, lunar and seasonal vertical migration in the deep western Gulf of Mexico evidenced from a long-term data series of acoustic backscatter

Progress In Oceanography ◽

10.1016/j.pocean.2021.102562 ◽

2021 ◽

pp. 102562

Author(s):

Laura Ursella ◽

Sara Pensieri ◽

Enric Pallàs-Sanz ◽

Sharon Z. Herzka ◽

Roberto Bozzano ◽

...

Keyword(s):

Gulf Of Mexico ◽

Vertical Migration ◽

Acoustic Backscatter ◽

Data Series ◽

Term Data

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Family feud: permanent group splitting in a highly philopatric mammal, the killer whale (Orcinus orca)

Behavioral Ecology and Sociobiology ◽

10.1007/s00265-021-02992-8 ◽

2021 ◽

Vol 75 (3) ◽

Author(s):

Eva H. Stredulinsky ◽

Chris T. Darimont ◽

Lance Barrett-Lennard ◽

Graeme M. Ellis ◽

John K. B. Ford

Keyword(s):

Killer Whale ◽

Group Structure ◽

Group Living ◽

Orcinus Orca ◽

Learning Approaches ◽

Killer Whales ◽

Internal Factors ◽

Individual Fitness ◽

Leadership Experience

Abstract For animals that tend to remain with their natal group rather than individually disperse, group sizes may become too large to benefit individual fitness. In such cases, group splitting (or fission) allows philopatric animals to form more optimal group sizes without sacrificing all familiar social relationships. Although permanent group splitting is observed in many mammals, it occurs relatively infrequently. Here, we use combined generalized modeling and machine learning approaches to provide a comprehensive examination of group splitting in a population of killer whales (Orcinus orca) that occurred over three decades. Fission occurred both along and across maternal lines, where animals dispersed in parallel with their closest maternal kin. Group splitting was more common: (1) in larger natal groups, (2) when the common maternal ancestor was no longer alive, and (3) among groups with greater substructuring. The death of a matriarch did not appear to immediately trigger splitting. Our data suggest intragroup competition for food, leadership experience and kinship are important factors that influence group splitting in this population. Our approach provides a foundation for future studies to examine the dynamics and consequences of matrilineal fission in killer whales and other taxa. Significance statement Group living among mammals often involves long-term social affiliation, strengthened by kinship and cooperative behaviours. As such, changes in group membership may have significant consequences for individuals’ fitness and a population’s genetic structure. Permanent group splitting is a complex and relatively rare phenomenon that has yet to be examined in detail in killer whales. In the context of a growing population, in which offspring of both sexes remain with their mothers for life, we provide the first in-depth examination of group splitting in killer whales, where splitting occurs both along and across maternal lines. We also undertake the first comprehensive assessment of how killer whale intragroup cohesion is influenced by both external and internal factors, including group structure, population and group demography, and resource abundance.

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Chances and challenges of a long-term data repository in multiple sclerosis: 20th birthday of the German MS registry

Scientific Reports ◽

10.1038/s41598-021-92722-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Lisa-Marie Ohle ◽

David Ellenberger ◽

Peter Flachenecker ◽

Tim Friede ◽

Judith Haas ◽

...

Keyword(s):

Multiple Sclerosis ◽

Sociodemographic Factors ◽

Healthcare Research ◽

Structure Design ◽

Data Repository ◽

Research Projects ◽

Real World Data ◽

Data Repositories ◽

Term Data

AbstractIn 2001, the German Multiple Sclerosis Society, facing lack of data, founded the German MS Registry (GMSR) as a long-term data repository for MS healthcare research. By the establishment of a network of participating neurological centres of different healthcare sectors across Germany, GMSR provides observational real-world data on long-term disease progression, sociodemographic factors, treatment and the healthcare status of people with MS. This paper aims to illustrate the framework of the GMSR. Structure, design and data quality processes as well as collaborations of the GMSR are presented. The registry’s dataset, status and results are discussed. As of 08 January 2021, 187 centres from different healthcare sectors participate in the GMSR. Following its infrastructure and dataset specification upgrades in 2014, more than 196,000 visits have been recorded relating to more than 33,000 persons with MS (PwMS). The GMSR enables monitoring of PwMS in Germany, supports scientific research projects, and collaborates with national and international MS data repositories and initiatives. With its recent pharmacovigilance extension, it aligns with EMA recommendations and helps to ensure early detection of therapy-related safety signals.

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