Biology subjects

Carromeu-Santos, A.

Publications and source records attributed to Carromeu-Santos, A..

3 recordsLinked to original sources

bioRxiv2022

Biogeographical history shapes evolution of reproduction in a global warming scenario

Adaptive evolution might be critical for animal populations to thrive on the fast-changing natural environments. Ectotherms are particularly vulnerable to global warming and, although their limited coping ability has been suggested, few real-time evolution experiments have directly accessed their evolutionary potential. Here, we report a long-term experimental evolution study addressing the evolution of thermal reaction norms, after [~]30 generations under different thermal environments. We analyzed the evolutionary dynamics of Drosophila subobscura populations as a function of the thermally variable environments in which they evolved and their distinct biogeographical background. Our results showed clear differences between the historically differentiated populations: while the northern D. subobscura populations showed a temporal increase in performance at higher temperatures, their southern counterparts presented the opposite pattern. This suggests that the northern populations might be better equipped to cope with the current rising temperatures. Remarkably, no effect of thermal selection was found. The lack of a clear long-term adaptive response at higher temperatures after evolution under a global warming scenario raises concerns about the evolutionary potential of ectotherms. Our results highlight the complex nature of thermal responses in face of environmental heterogeneity and emphasize the importance of considering intra-specific variation in thermal evolution studies.

evolutionary biology↗

bioRxiv2021

No evidence for short-term evolutionary response to a warming environment in Drosophila

Adaptive evolution is key in mediating responses to climate change. Such evolution will expectedly lead to changes in the populations thermal reaction norm and improve their ability to cope with stressful conditions. Conversely, constraints of different nature might limit the adaptive response. Here, we test these expectations by performing a real-time evolution experiment in historically differentiated Drosophila subobscura populations. We address the phenotypic changes of flies evolving for nine generations in a daily fluctuating environment with average constant temperature, or a warming environment with increasing average and amplitude temperature across generations. Our results showed that (1) evolution under a global warming scenario has not led, so far, to a noticeable change in the thermal response; (2) historical background appears to be affecting the responses of populations under the warming environment, particularly at higher temperatures; (3) thermal reaction norms are trait-dependent: while lifelong exposure to low temperature decreases fecundity and productivity but not viability, high temperature causes negative transgenerational effects on productivity and viability, even though fecundity remains high. These findings raise concerns about the short-term efficiency of adaptive responses to the current changing climate.

evolutionary biology↗

bioRxiv2020

High developmental temperature leads to low reproduction despite adult temperature

Phenotypic plasticity can be an important tool in helping organisms to cope with changing thermal conditions and it may show an interdependency between life-stages. For instance, exposure to stressful temperatures during development can trigger a positive plastic response in adults. In this study, we analyse the thermal plastic response of laboratory populations of Drosophila subobscura, derived from two contrasting latitudes of the European cline. We measured fecundity characters in the experimental populations after exposure to five thermal treatments, with different combinations of developmental and adult temperatures (14{degrees}C, 18{degrees}C or 26{degrees}C). We ask whether (1) adult performance is enhanced (or reduced) by exposing flies to higher (or lower) temperatures during development only; (2) flies raised at lower temperatures outperform those developed at higher ones, supporting the "colder is better" hypothesis; (3) there is a cumulative effect on adult performance of exposing both juveniles and adults to higher (or lower) temperatures; (4) there is any evidence for historical effects on adult performance. Our main findings show that (1) higher developmental temperatures led to low reproductive performance regardless of adult temperature, while at lower temperatures reduced performance only occurred when cold conditions were persistent across juvenile and adult stage; (2) flies raised at lower temperatures did not always outperform those developed at other temperatures; (3) there was no (negative) cumulative effect of exposing both juveniles and adults to higher temperatures; (4) both latitudinal populations showed similar thermal plasticity patterns. The negative effect of high developmental temperature on reproductive performance, regardless of adult temperature, highlights the developmental stage as a critical and most vulnerable stage to climate change and associated heat waves.

evolutionary biology↗