Geographical variation in population demography and life history traits of Tecate cypress (Hesperocyparis forbesii) suggests a fire regime gradient across the USA–Mexico border

AbstractAmphibian biodiversity is declining globally, with over 40% of species being considered threatened to become extinct. Crucial to the success of conservation initiatives are a comprehensive understanding of life history and reproductive ecology of target species. Here we provide an overview of the Pseudacris genus, including breeding behaviour, reproduction, development, survival and longevity. We present an updated distribution map of the 18 species found throughout North America. We also summarize the conservation status at the national and subnational (state, provincial, and territorial) levels, in Canada, USA, and Mexico, to evaluate the relationship between life history traits and extinction risk. Results show a high degree of consistency in the life history traits of Pseudacris species considering their relative diversity and wide distribution in North America. However, data are lacking for several species, particularly in the Fat Frog and West Coast clades, causing some uncertainties and discrepancies in the literature. We also found that the most threatened populations of chorus frog were located in the east coast of the USA, potentially as a result of increased levels of anthropogenic disturbance. We suggest that the similarities in life history traits among chorus frog species provides an opportunity for collaboration and united efforts for the conservation of the genus.

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Genetic consequences of being a dwarf: do evolutionary changes in life-history traits influence gene flow patterns in populations of the world’s smallest goldenrod?

Annals of Botany ◽

10.1093/aob/mcaa062 ◽

2020 ◽

Vol 126 (1) ◽

pp. 163-177

Author(s):

Shota Sakaguchi ◽

Atsushi J Nagano ◽

Masaki Yasugi ◽

Hiroshi Kudoh ◽

Naoko Ishikawa ◽

...

Keyword(s):

Life History ◽

Gene Flow ◽

Genetic Structure ◽

Seed Dispersal ◽

Dna Sequences ◽

Life History Traits ◽

Population Divergence ◽

Population Demography ◽

Long Distance ◽

Yakushima Island

Abstract Background and Aims Contrasting life-history traits can evolve through generations of dwarf plant ecotypes, yet such phenotypic changes often involve decreased plant size and reproductive allocation, which can configure seed dispersal patterns and, subsequently, population demography. Therefore, evolutionary transitions to dwarfism can represent good study systems to test the roles of life-history traits in population demography by comparing genetic structure between related but phenotypically divergent ecotypes. Methods In this study, we examined an ecotypic taxon pair of the world’s smallest goldenrod (stem height 2.6 cm) in alpine habitats and its closely related lowland taxon (30–40 cm) found on Yakushima Island, Japan. Genetic variation in chloroplast DNA sequences, nuclear microsatellites and genome-wide single-nucleotide polymorphisms were used to investigate 197 samples from 16 populations, to infer the population genetic demography and compare local genetic structure of the ecotypes. Key Results We found a pronounced level of genetic differentiation among alpine dwarf populations, which were much less geographically isolated than their lowland counterparts. In particular, several neighbouring dwarf populations (located ~500 m apart) harboured completely different sets of chloroplast haplotypes and nuclear genetic clusters. Demographic modelling revealed that the dwarf populations have not exchanged genes at significant levels after population divergence. Conclusions These lines of evidence suggest that substantial effects of genetic drift have operated on these dwarf populations. The low-growing stature and reduced fecundity (only 3.1 heads per plant) of the dwarf plants may have reduced gene flow and rare long-distance seed dispersal among habitat patches, although the effects of life-history traits require further evaluation using ecological approaches.

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Adaptation of an Invasive Pest to Novel Environments: Life History Traits of Drosophila suzukii in Coastal and Mainland Areas of Greece during Overwintering

Biology ◽

10.3390/biology10080727 ◽

2021 ◽

Vol 10 (8) ◽

pp. 727

Author(s):

Stella A. Papanastasiou ◽

Vasilis G. Rodovitis ◽

Eleni Verykouki ◽

Evmorfia P. Bataka ◽

Nikos T. Papadopoulos

Keyword(s):

Life History ◽

Coastal Area ◽

Life History Traits ◽

Survival Rates ◽

Reproductive Activity ◽

Climatic Conditions ◽

Invasive Pest ◽

High Survival ◽

Drosophila Suzukii ◽

The Usa

Drosophila suzukii is a polyphagous pest of small and soft fruit, originating from Asia, which has spread and established in Europe and the USA. Adults exhibit seasonal phenotypes, i.e., summer morphs (SM) and winter morphs (WM) to cope with fluctuating environmental conditions. WM have a darker cuticle and larger wings compared to SM, while WM females experience reproductive dormancy. We studied the life history traits (lifespan, female reproductive status and number of produced offspring) of WM and SM that were exposed to winter field conditions of a coastal and a mainland agricultural area, with mild and cold winter climates, respectively. Mated adults of each phenotype were individually placed in vials bearing nutritional/oviposition substrate, and transferred to the field from November 2019 to May 2020, when the death of the last individual was recorded. Almost all SM females (90%) and no WM female carried mature ovarioles before being transferred to the field. WM exhibited a longer lifespan than SM adjusting for location and sex. Differences in survival between the two phenotypes were more pronounced for adults kept in the mainland area. The majority of SM females produced offspring during overwintering in the mild coastal area, but only a few SM were reproductively active in the cold mainland area. Some WM females produced progeny during overwintering in the mild conditions of the coastal area, but all WM females were in reproductive arrest in the mainland area. Overwintering females in the coastal area had a shorter lifespan and produced more progeny than those kept in the mainland area. High survival rates of WM provide indications of the successful performance of this phenotype in the adverse conditions of the cold climates. Additionally, the continuous reproductive activity of SM females and the onset of progeny production by WM females during overwintering in the coastal area indicate that the insect remains reproductively active throughout the year in areas with mild climatic conditions. Our findings support the successful adaptation of D. suzukii in both areas tested and can be used for the development of area-specific population models, based on the prevailing climatic conditions.

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