scholarly journals Patterns of genomic diversification reflect differences in life history and reproductive biology between figs (Ficus) and the stone oaks (Lithocarpus)

Genome ◽  
2017 ◽  
Vol 60 (9) ◽  
pp. 756-761 ◽  
Author(s):  
Chai-Shian Kua ◽  
Charles H. Cannon
Keyword(s):  
Life History ◽  
Evolutionary Relationship ◽  
Genomic Diversity ◽  
Evolutionary Strategies ◽  
Life History Strategies ◽  
Wide Range ◽  
Genomic Divergence ◽  
History Of ◽  
Background History ◽  
Diverse Groups

One of the remarkable aspects of the tremendous biodiversity found in tropical forests is the wide range of evolutionary strategies that have produced this diversity, indicating many paths to diversification. We compare two diverse groups of trees with profoundly different biologies to discover whether these differences are reflected in their genomes. Ficus (Moraceae), with its complex co-evolutionary relationship with obligate pollinating wasps, produces copious tiny seeds that are widely dispersed. Lithocarpus (Fagaceae), with generalized insect pollination, produces large seeds that are poorly dispersed. We hypothesize that these different reproductive biologies and life history strategies should have a profound impact on the basic properties of genomic divergence within each genus. Using shallow whole genome sequencing for six species of Ficus, seven species of Lithocarpus, and three outgroups, we examined overall genomic diversity, how it is shared among the species within each genus, and the fraction of this shared diversity that agrees with the major phylogenetic pattern. A substantially larger fraction of the genome is shared among species of Lithocarpus, a considerable amount of this shared diversity was incongruent with the general background history of the genomes, and each fig species possessed a substantially larger fraction of unique diversity than Lithocarpus.

scholarly journals Geography is more important than life history in the recent diversification of the tiger salamander complex

2020 ◽  
Author(s):  
Kathryn M. Everson ◽  
Levi N. Gray ◽  
Angela G. Jones ◽  
Nicolette M. Lawrence ◽  
Mary E. Foley ◽  
...  
Keyword(s):  
Life History ◽  
Gene Flow ◽  
Life History Strategies ◽  
Conservation Priorities ◽  
Tiger Salamander ◽  
Life History Variation ◽  
Wide Range ◽  
History Of ◽  
Lineage Divergence ◽  
Salamander Species

AbstractThe North American tiger salamander species complex, including its flagship species the axolotl, has long been a source of biological fascination. The complex exhibits a wide range of variation in developmental life history strategies, including populations and individuals that undergo metamorphosis and those able to forego metamorphosis and retain a larval, aquatic lifestyle (i.e., paedomorphosis). Such disparate life history strategies are assumed to cause populations to become reproductively isolated, but the degree to which they have actually shaped population- and species-level boundaries is poorly understood. Using a large multi-locus dataset from hundreds of samples across North America, we identified genetic clusters with clear signs of admixture across the geographic range of the tiger salamander complex. Population clusters often contain a mixture of paedomorphic and metamorphic taxa, and we conclude that geography has played a large role in driving lineage divergence relative to obligate paedomorphosis in this system. This conclusion is bolstered by model-based analyses demonstrating gene flow between metamorphic and paedomorphic populations. Even the axolotl, a paedomorphic species with an isolated native range, apparently has a history of gene flow with its neighboring populations. This fine-scale genetic perspective on life-history variation establishes a framework for understanding how plasticity, local adaptation, and gene flow contribute to lineage divergence. The axolotl is currently used as the vertebrate model system in regenerative biology, and our findings chart a course for more informed use of these and other tiger salamander species in experimental and field research, including conservation priorities.Significance StatementPopulation structure and speciation are shaped by a variety of biotic and abiotic factors. In the tiger salamander complex, one factor that may influence diversification is life history: some taxa are obligately paedomorphic–a condition where adults maintain an aquatic, larval phenotype–while others are facultatively paedomorphic or entirely metamorphic. Using a large multi-locus dataset, we found evidence of gene flow and/or panmixia between obligately and facultatively paedomorphic taxa, suggesting that an obligately paedomorphic life history is not a strong driver of speciation in the tiger salamander complex. We also recovered a history of gene flow between the critically endangered axolotl and its neighboring populations, providing important information for its conservation and captive management.

scholarly journals Contrasting effects of climate change on seasonal survival of a hibernating mammal

2020 ◽  
Vol 117 (30) ◽  
pp. 18119-18126 ◽  
Author(s):  
Line S. Cordes ◽  
Daniel T. Blumstein ◽  
Kenneth B. Armitage ◽  
Paul J. CaraDonna ◽  
Dylan Z. Childs ◽  
...  
Keyword(s):  
Climate Change ◽  
Population Dynamics ◽  
Life History ◽  
Environmental Conditions ◽  
Temporal Trends ◽  
Life History Strategies ◽  
Environmental Drivers ◽  
Age Classes ◽  
History Of ◽  
Colorado Rocky Mountains

Seasonal environmental conditions shape the behavior and life history of virtually all organisms. Climate change is modifying these seasonal environmental conditions, which threatens to disrupt population dynamics. It is conceivable that climatic changes may be beneficial in one season but result in detrimental conditions in another because life-history strategies vary between these time periods. We analyzed the temporal trends in seasonal survival of yellow-bellied marmots (Marmota flaviventer) and explored the environmental drivers using a 40-y dataset from the Colorado Rocky Mountains (USA). Trends in survival revealed divergent seasonal patterns, which were similar across age-classes. Marmot survival declined during winter but generally increased during summer. Interestingly, different environmental factors appeared to drive survival trends across age-classes. Winter survival was largely driven by conditions during the preceding summer and the effect of continued climate change was likely to be mainly negative, whereas the likely outcome of continued climate change on summer survival was generally positive. This study illustrates that seasonal demographic responses need disentangling to accurately forecast the impacts of climate change on animal population dynamics.

scholarly journals Human Life History Strategies

2016 ◽  
Vol 15 (1) ◽  
pp. 147470491667734 ◽  
Author(s):  
Kristine J. Chua ◽  
Aaron W. Lukaszewski ◽  
DeMond M. Grant ◽  
Oliver Sng
Keyword(s):  
Life History ◽  
Health Status ◽  
Latent Variable ◽  
Structural Equation Models ◽  
Human Life ◽  
Mating Strategies ◽  
Life History Strategies ◽  
Environmental Cues ◽  
Behavioral Phenotypes ◽  
Wide Range

Human life history (LH) strategies are theoretically regulated by developmental exposure to environmental cues that ancestrally predicted LH-relevant world states (e.g., risk of morbidity–mortality). Recent modeling work has raised the question of whether the association of childhood family factors with adult LH variation arises via (i) direct sampling of external environmental cues during development and/or (ii) calibration of LH strategies to internal somatic condition (i.e., health), which itself reflects exposure to variably favorable environments. The present research tested between these possibilities through three online surveys involving a total of over 26,000 participants. Participants completed questionnaires assessing components of self-reported environmental harshness (i.e., socioeconomic status, family neglect, and neighborhood crime), health status, and various LH-related psychological and behavioral phenotypes (e.g., mating strategies, paranoia, and anxiety), modeled as a unidimensional latent variable. Structural equation models suggested that exposure to harsh ecologies had direct effects on latent LH strategy as well as indirect effects on latent LH strategy mediated via health status. These findings suggest that human LH strategies may be calibrated to both external and internal cues and that such calibrational effects manifest in a wide range of psychological and behavioral phenotypes.

Attachment of the Coral Caryophyllia Smithii S. & B. to Tubes of the Polychaete Ditrupa Arietina (Müller) and other Substrates

1976 ◽  
Vol 56 (2) ◽  
pp. 291-303 ◽  
Author(s):  
John B. Wilson
Keyword(s):  
Life History ◽  
Early Growth ◽  
Soft Sediments ◽  
Wide Range ◽  
Growth History ◽  
History Of

INTRODUCTIONLittle is known about the early growth history of solitary corals in relation to the substrates to which they are attached. An understanding of this relationship between coral and substrate, and of how it may change throughout the life of the coral, is particularly important in studies of the life history and ecology of solitary corals living in sand and other soft sediments. A knowledge of the variety of different substrates to which solitary corals are attached in the wide range of different environments in which they live is also of importance to the palaeontologist when attempting palaeoecological interpretation of transported coral debris.

scholarly journals The influence of initial developmental status on the life-history of sea trout (Salmo trutta)

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Diego del Villar-Guerra ◽  
Martin H. Larsen ◽  
Henrik Baktoft ◽  
Anders Koed ◽  
Kim Aarestrup
Keyword(s):  
Life History ◽  
Salmo Trutta ◽  
Return Rate ◽  
Life History Strategies ◽  
Passive Integrated Transponder ◽  
Marine Life ◽  
Sea Trout ◽  
Osmoregulatory Capacity ◽  
History Of ◽  
One Year

Abstract Spring migrating sea trout juveniles can be classified as parr, pre-smolt or smolt based on body morphology and osmoregulatory capacity. In this respect, parr are assumed to be less prepared for a marine life and to have lower survival at sea than pre-smolts and smolts. However, the behaviour and survival of these trout phenotypes upon entering the sea is not well known. Using passive integrated transponder telemetry, this study found that the return rate from the sea to the natal river was higher for parr compared to pre-smolts and smolts. Additionally, trout classified as parr generally migrated earlier to the sea and a larger proportion returned to the river after less than one year at sea. The daily mortality rate at sea was comparable among the different phenotypes of trout, suggesting that the higher proportion of returning parr to the river was linked to their shorter duration at sea. These results provide evidence of different life-history strategies for seaward-migrating juvenile sea trout, ultimately affecting their return rate to the natal river. Investigations failing to consider downstream migrating parr and pre-smolts risks neglecting a large part of the anadromous population and may result in inaccurate assessments of sea trout stocks in rivers.

scholarly journals Background History, Clinical Presentation and Laboratory Profile in Cases of Suspected Neurometabolic Disorders

2016 ◽  
Vol 39 (1) ◽  
pp. 24-29 ◽  
Author(s):  
Mustafa Mahbub ◽  
AZM Mosiul Azam ◽  
Suraj C Mazumder ◽  
Bithi Debnath ◽  
Naila Zaman Khan
Keyword(s):  
Clinical Presentation ◽  
Clinical Manifestations ◽  
Normal Activity ◽  
New Delhi ◽  
Laboratory Findings ◽  
Neurometabolic Disorders ◽  
Wide Range ◽  
History Of ◽  
Background History ◽  
Biotinidase Activity

Background : Neurometabolic disorders (NMD) in children may present at any age with a wide range of clinical manifestations. Unexplained or intractable seizure is one of the important associations. Consanguinity, regression of development and sibling death are the clues to suspect neurometabolic disorders when laboratory support is limited. Laboratory findings however, provide the confirmatory diagnosis which is unavailable in Bangladesh.Objectives : To determine the association of consanguinity, regression of development, seizures, EEG findings and other laboratory investigations in children suspected to have neurometabolic disorders and to aid clinicians working in resourcepoor countries.Methodology : A retrospective analysis was done from the records of the patients suspected to have neurometabolic disorders admitted in the department of Neurosciences, Dhaka Shishu Hospital, Dhaka during the period of July 2007 to February 2011. Tandem Mass Spectrometry (TMS), biotinidase activity and other enzyme assay were done through a private laboratory in New Delhi, India.Results : Total 128 children were studied and the parents of 39 (31%) had history of consanguineous marriage. Seizure was associated with 96 (75%) children and abnormal EEG findings were recorded in 83 (65%). Plasma ammonia was done in 98 cases and found to be increased in 53 (54%) cases. Plasma lactate was done in 94 cases and found high in 40 (43%). TMS were done in 111 (85%) children and abnormality were found in 70 (63%) cases. Serum biotinidase activity was advised for 41 children as per TMS result and measured in 25 children of which deficient activity was found in 17(68%); borderline in 4 (16%) and normal activity in 4 (16%) cases.Conclusion: Background history and clinical presentation followed by stepwise laboratory investigation is necessary to identify neurometabolic disorders. Early and appropriate intervention can reduce neurodisability in many situations.Bangladesh J Child Health 2015; VOL 39 (1) :24-29

“Girlie Man, Manly Girl, It’s all the Same to me”

2019 ◽  
pp. 22-35
Keyword(s):  
Life History ◽  
Male Characters ◽  
Drag King ◽  
Historical Archive ◽  
Wide Range ◽  
Queer Culture ◽  
Current Events ◽  
History Of ◽  
Community Shifts ◽  
Do So

First published in 1983 in Womanews, and later widely syndicated, Alison Bechdel’s Dykes To Watch Out For (DTWOF) series not only created an unparalleled historical archive of queer culture, it also shaped both the lesbian comix and queer comics that came after it in remarkable ways. Through her use of a wide range of characters having pointed conversations about then-current events and politics, debating identity, desire, and shifting representation, or simply going out to dinner at Café Topaz, the local vegetarian restaurant, Bechdel catalogues a life history of these lesbians and their community—even as that community shifts in unanticipated ways, as our understanding of binary gender shifts and continues to do so today. For a strip that initially included no men, DWTOF ended up including a number of male characters in order to explore what “male” meant through drag king culture, non-binary characters, and characters who identify as transgender.

Life in the Slow Lane: Ecology and Conservation of Long-Lived Marine Animals

1999 ◽  
Keyword(s):  
Life History ◽  
Management Plan ◽  
Fishing Effort ◽  
Life History Strategies ◽  
Shark Species ◽  
Fishing Pressure ◽  
Marine Animals ◽  
Selective Pressures ◽  
Stock Assessments ◽  
History Of

<em> Abstract.</em>—Sharks have the reputation of being particularly vulnerable to fishing pressure, a fact attributed to their generally ‘<EM> K</EM>-selected’ life history strategies. The history of shark fisheries is not encouraging, and their poor record of sustainability is compounded by the fact that few countries have any form of management for these resources. The Australian Southern Shark Fishery provides an example of a well-studied shark fishery with a long history of exploitation that has been under a management plan for some ten years. This fishery is unique in that it exploits, under a similar fishing regime, two similar target shark species that show very different responses to fishing pressure. Stock assessments suggest that under current fishing effort the catch of one species is sustainable while the other species is overexploited. The vulnerability of the two species to the fishing gear is similar but their biological productivity is very different. The selective pressures that may have given rise to these different life history strategies are discussed.

scholarly journals Cell Size Distributions of Soil Bacterial and Archaeal Taxa

2013 ◽  
Vol 79 (24) ◽  
pp. 7610-7617 ◽  
Author(s):  
Maria C. Portillo ◽  
Jonathan W. Leff ◽  
Christian L. Lauber ◽  
Noah Fierer
Keyword(s):  
Life History ◽  
Cell Size ◽  
High Throughput Sequencing ◽  
Size Fraction ◽  
Life History Strategies ◽  
Rrna Gene ◽  
Average Cell ◽  
Content Type ◽  
Size Fractions ◽  
Wide Range

ABSTRACTCell size is a key ecological trait of soil microorganisms that determines a wide range of life history attributes, including the efficiency of nutrient acquisition. However, because of the methodological issues associated with determining cell sizesin situ, we have a limited understanding of how cell abundances vary across cell size fractions and whether certain microbial taxa have consistently smaller cells than other taxa. In this study, we extracted cells from three distinct soils and fractionated them into seven size ranges (5 μm to 0.2 μm) by filtration. Cell abundances in each size fraction were determined by direct microscopy, with the taxonomic composition of each size fraction determined by high-throughput sequencing of the 16S rRNA gene. Most of the cells were smaller than cells typically grown in culture, with 59 to 67% of cells <1.2 μm in diameter. Furthermore, each size fraction harbored distinct bacterial and archaeal communities in each of the three soils, and many of the taxa exhibited distinct size distribution patterns, with the smaller size fractions having higher relative abundances of taxa that are rare or poorly characterized (includingAcidobacteria,Gemmatimonadetes,Crenarchaeota,Verrucomicrobia, andElusimicrobia). In general, there was a direct relationship between average cell size and culturability, with those soil taxa that are poorly represented in culture collections tending to be smaller. Size fractionation not only provides important insight into the life history strategies of soil microbial taxa but also is a useful tool to enable more focused investigations into those taxa that remain poorly characterized.

scholarly journals A new maximum body size record for the Berry Cave Salamander (Gyrinophilus gulolineatus) and genus Gyrinophilus (Caudata, Plethodontidae) with a comment on body size in plethodontid salamanders

2018 ◽  
Vol 28 ◽  
pp. 29-38
Author(s):  
Nicholas S. Gladstone ◽  
Evin T. Carter ◽  
K. Denise Kendall Niemiller ◽  
Lindsey E. Hayter ◽  
Matthew L. Niemiller
Keyword(s):  
Life History ◽  
Body Size ◽  
Large Body ◽  
The United States ◽  
Life History Strategies ◽  
Large Individual ◽  
Plethodontid Salamander ◽  
Plethodontid Salamanders ◽  
The Family ◽  
History Of

Lungless salamanders in the family Plethodontidae exhibit an impressive array of life history strategies and occur in a diversity of habitats, including caves. However, relationships between life history, habitat, and body size remain largely unresolved. During an ongoing study on the demography and life history of the paedomorphic, cave-obligate Berry Cave Salamander (Gyrinophilusgulolineatus, Brandon 1965), we discovered an exceptionally large individual from the type locality, Berry Cave, Roane County, Tennessee, USA. This salamander measured 145 mm in body length and represents not only the largest G.gulolineatus and Gyrinophilus ever reported, but also the largest plethodontid salamander in the United States. We discuss large body size in G.gulolineatus and compare body size in other large plethodontid salamanders in relation to life history and habitat.

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