A systematic map of studies testing the relationship between temperature and animal reproduction

Funding: This work was funded by the European Society for Evolution (which funds a Special Topic Network on Evolutionary Ecology of Thermal Fertility Limits to CF, AB, RRS and TARP), the Natural Environment Research Council (NE/P002692/1 to TARP, AB and RRS, NE/X011550/1 to LRD and TARP), the Biotechnology and \Biological Sciences Research Council (BB/W016753/1 to AB, TARP and RRS) and a Heisenberg fellowship from the German Research Foundation (FR 2973/11-1 to CF).1. Exposure to extreme temperatures can negatively affect animal reproduction, by disrupting the ability of individuals to produce any offspring (fertility), or the number of offspring produced by fertile individuals (fecundity). This has important ecological consequences, because reproduction is the ultimate measure of population fitness: a reduction in reproductive output lowers the population growth rate and increases the extinction risk. Despite this importance, there have been no large‐scale summaries of the evidence for effect of temperature on reproduction. 2. We provide a systematic map of studies testing the relationship between temperature and animal reproduction. We systematically searched for published studies that statistically test for a direct link between temperature and animal reproduction, in terms of fertility, fecundity or indirect measures of reproductive potential (gamete and gonad traits). 3. Overall, we collated a large and rich evidence base, with 1654 papers that met our inclusion criteria, encompassing 1191 species. 4. The map revealed several important research gaps. Insects made up almost half of the dataset, but reptiles and amphibians were uncommon, as were non‐arthropod invertebrates. Fecundity was the most common reproductive trait examined, and relatively few studies measured fertility. It was uncommon for experimental studies to test exposure of different life stages, exposure to short‐term heat or cold shock, exposure to temperature fluctuations, or to independently assess male and female effects. Studies were most often published in journals focusing on entomology and pest control, ecology and evolution, aquaculture and fisheries science, and marine biology. Finally, while individuals were sampled from every continent, there was a strong sampling bias towards mid‐latitudes in the Northern Hemisphere, such that the tropics and polar regions are less well sampled. 5. This map reveals a rich literature of studies testing the relationship between temperature and animal reproduction, but also uncovers substantial missing treatment of taxa, traits, and thermal regimes. This database will provide a valuable resource for future quantitative meta‐analyses, and direct future studies aiming to fill identified gaps.Publisher PDFPeer reviewe

A systematic map of studies testing the relationship between temperature and animal reproduction

DATA AVAILABILITY STATEMENT ; All data are available on Figshare: https://doi.org/10.6084/m9.figshare.24182745.v1 (Dougherty et al., 2023).SUPPORTING INFORMATION : FIGURE S1: Phylogenetic tree showing the relationship between the 1191 species in the systematic map. Note that branch lengths are standardised because branch length information was not available.Exposure to extreme temperatures can negatively affect animal reproduction, by disrupting the ability of individuals to produce any offspring (fertility), or the number of offspring produced by fertile individuals (fecundity). This has important ecological consequences, because reproduction is the ultimate measure of population fitness: a reduction in reproductive output lowers the population growth rate and increases the extinction risk. Despite this importance, there have been no large-scale summaries of the evidence for effect of temperature on reproduction. We provide a systematic map of studies testing the relationship between temperature and animal reproduction. We systematically searched for published studies that statistically test for a direct link between temperature and animal reproduction, in terms of fertility, fecundity or indirect measures of reproductive potential (gamete and gonad traits). Overall, we collated a large and rich evidence base, with 1654 papers that met our inclusion criteria, encompassing 1191 species. The map revealed several important research gaps. Insects made up almost half of the dataset, but reptiles and amphibians were uncommon, as were non-arthropod invertebrates. Fecundity was the most common reproductive trait examined, and relatively few studies measured fertility. It was uncommon for experimental studies to test exposure of different life stages, exposure to short-term heat or cold shock, exposure to temperature fluctuations, or to independently assess male and female effects. Studies were most often published in journals focusing on entomology and pest control, ecology and evolution, aquaculture and fisheries science, and marine biology. Finally, while individuals were sampled from every continent, there was a strong sampling bias towards mid-latitudes in the Northern Hemisphere, such that the tropics and polar regions are less well sampled. This map reveals a rich literature of studies testing the relationship between temperature and animal reproduction, but also uncovers substantial missing treatment of taxa, traits, and thermal regimes. This database will provide a valuable resource for future quantitative meta-analyses, and direct future studies aiming to fill identified gaps.Deutsche Forschungsgemeinschaft; Natural Environment Research Council; European Society for Evolutionary Biology; Biotechnology and Biological Sciences Research Council.http://www.wileyonlinelibrary.com/journal/eso3hj2024Zoology and EntomologySDG-03:Good heatlh and well-bein

New perspectives on meeting and mating

In this special issue, several authors have been invited in order to provide new perspectives on a set of phenomena related to sexual reproduction. The idea has been to offer a journey that explores sexual communication and mating practices in a wide range of animals, with a particular focus on the lesser-known model organisms as well as on recent and unexpected findings in well-established systems. As a result, the papers within this issue span a taxonomic range of organisms with a wide variety of mating systems. While this may seem rather heterogeneous, taken together this collection is intended to provide a more integrative view of sexual selection. The topics range from fundamental questions such as the diversity of processes targeted by sexual selection, to mate assessment, chemical communication and sexual conflict. As an ensemble these studies challenge some of the general assumptions, look beyond the traditional division of sex roles and place underexposed topics in the spotlight..

Dataset

The effects of diet on parental life-history traits, the effects of mating partner on resource allocation and the effects of parental diet on offspring life-history traits, are organized in four worksheets. Please, note that the shortcuts H and L in the dataset, denote the high and low diet, respectively

Table S1 from Sublethal heat reduces overall reproductive investment and male allocation in a simultaneously hermaphroditic snail species

The exposure to sub lethally high temperature reduces reproductive performance in diverse organisms. Although this effect has been particularly emphasized for males or male reproductive functioning, it remains largely unknown whether the effect of heat on fertility is sex-specific. Here we examined the impact of sub lethally high temperature on male and female functions in a simultaneously hermaphroditic snail species, Lymnaea stagnalis. Examining hermaphrodites is useful to evaluate the sex-specific impacts of heat exposure, since they possess male and female functions within a single individual, sharing genetic and environmental factors. Moreover, previously developed sex allocation theory allows us to compare the differential performance of sex functions. In this study, we exposed snails to 20°C (control), 24°C and 28°C for 14 days and assessed their egg and sperm production, sperm transfer, mating behaviour and growth. Both types of gamete production were significantly reduced by higher temperature, leading to an overall reduction of reproductive investment. By quantifying sex allocation, we furthermore revealed that the heat-stressed snails reduced the relative investment in their male function. This study illustrates that examining simultaneous hermaphrodites can provide significant insights for the impact of heat, and the proximate mechanism, on reproduction in diverse organisms

Love at first sniff: a spermatophore-associated pheromone mediates partner attraction in a collembolan species

Mate choice is essential in most animals, as a good choice of mating partner largely determines reproductive success. Much evidence shows that olfactory cues play an important role in mate choice. However, the integration of chemical, visual and acoustic cues, often used when both partners meet, makes it hard to test whether olfaction alone can mediate reproductive decisions. Interestingly, several invertebrates have adopted a mating system where males deposit their sperm (packed in spermatophores) in the environment for females to pick up with no visual contact between the sexes. In this case the male cue is conveyed by the spermatophore only. Earlier studies on a species with indirect sperm transfer, the soil arthropod Orchesella cincta, showed that, even in these animals, female choice exists. In this study, we tested whether chemical cues provided by the spermatophores mediate this female choice. Chemical analysis of spermatophore extracts revealed that (Z)-14-tricosenol is the main compound in the male spermatophores and this compound attracted females in olfactometer bioassays. Our finding suggests that (Z)-14-tricosenol is thus a pheromone component, which is sufficient for female attraction. This is the first report of a spermatophore-associated sex pheromone in a species performing indirect sperm transfer

Radiochemistry on chip: towards dose-on-demand synthesis of PET radiopharmaceuticals

We have developed an integrated microfluidic platform for producing 2-[¹⁸F]-fluoro-2-deoxy-D-glucose (¹⁸F-FDG) in continuous flow from a single bolus of radioactive isotope solution, with constant product yields achieved throughout the operation that were comparable to those reported for commercially available vessel-based synthesisers (40–80%). The system would allow researchers to obtain radiopharmaceuticals in a dose-on-demand setting within a few minutes. The flexible architecture of the platform, based on a modular design, can potentially be applied to the synthesis of other radiotracers that require a two-step synthetic approach, and may be adaptable to more complex synthetic routes by implementing additional modules. It can therefore be employed for standard synthesis protocols as well as for research and development of new radiopharmaceuticals