scholarly journals Thermal Preferences of Cowpea Seed Beetles (Callosobruchus maculatus): Effects of Sex and Nuptial Gift Transfers

Insects ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 310
Author(s):  
Dariusz Krzysztof Małek ◽  
Marcin Czarnoleski
Keyword(s):  
Water Balance ◽  
Callosobruchus Maculatus ◽  
Thermal Environment ◽  
Nuptial Gift ◽  
Thermal Preference ◽  
Nuptial Gifts ◽  
Insect Performance ◽  
Evaporative Water ◽  
Thermal Preferences ◽  
Seed Beetles

The thermal environment influences insect performance, but the factors affecting insect thermal preferences are rarely studied. We studied Callosobruchus maculatus seed beetles and hypothesized that thermal preferences are influenced by water balance, with individuals with limited water reserves preferring cooler habitats to reduce evaporative water loss. Adult C. maculatus, in their flightless morph, do not consume food or water, but a copulating male provides a female with a nuptial gift of ejaculate containing nutrients and water. We hypothesized that gift recipients would prefer warmer habitats than gift donors and that both sexes would plastically adjust their thermal preferences according to the size of the transferred gift. We measured the thermal preference in each sex in individuals that were mated once or were unmated. In the mated group, we measured the sizes of the nuptial gifts and calculated proportional body mass changes in each mate during copulation. Supporting the role of water balance in thermal preference, females preferred warmer habitats than males. Nevertheless, thermal preferences in either sex were not affected by mating status or gift size. It is likely that high rates of mating and gift transfers in C. maculatus living under natural conditions promoted the evolution of constitutive sex-dependent thermal preferences.

scholarly journals Bearded dragons (Pogona vitticeps) with reduced scalation lose water faster but do not have substantially different thermal preferences

2021 ◽  
Author(s):  
Nicholas B. Sakich ◽  
Glenn J. Tattersall
Keyword(s):  
Water Loss ◽  
Evaporative Water Loss ◽  
Thermal Preference ◽  
Evaporative Water ◽  
Pet Trade ◽  
Instantaneous Rate ◽  
Bearded Dragon ◽  
Pogona Vitticeps ◽  
Thermal Preferences ◽  
Applied Fields

Whether scales reduce cutaneous evaporative water loss in lepidosaur reptiles (Superorder Lepidosauria) such as lizards and snakes has been a contentious issue for nearly half a century. Furthermore, while many studies have looked at whether dehydration affects thermal preference in lepidosaurs, far fewer have examined whether normally hydrated lepidosaurs can assess their instantaneous rate of evaporative water loss and adjust their thermal preference to compensate in an adaptive manner. We tested both of these hypotheses using three captive-bred phenotypes of bearded dragon (Pogona vitticeps) sourced from the pet trade: ‘Wild Types’ with normal scalation, ‘Leatherbacks’ exhibiting scales of reduced prominence, and scaleless bearded dragons referred to as ‘Silkbacks’. Silkbacks on average lost water evaporatively at about twice the rate that Wild Types did. Leatherbacks on average were closer in their rates of evaporative water loss to Silkbacks than they were to Wild Types. Additionally, very small (at most ∼1°C) differences in thermal preference existed between the three phenotypes that were not statistically significant. This suggests a lack of plasticity in thermal preference in response to an increase in rate of evaporative water loss, and may be reflective of a thermal ‘strategy’ as employed by thermoregulating bearded dragons that prioritises immediate thermal benefits over the threat of future dehydration. The results of this study bolster an often-discounted hypothesis regarding the present adaptive function of scales and have implications for the applied fields of animal welfare and conservation.

scholarly journals The shield effect: nuptial gifts protect males against pre-copulatory sexual cannibalism

2016 ◽  
Vol 12 (5) ◽  
pp. 20151082 ◽  
Author(s):  
Søren Toft ◽  
Maria J. Albo
Keyword(s):  
Indirect Evidence ◽  
Experimental Tests ◽  
Female Aggression ◽  
Sexual Cannibalism ◽  
Nuptial Gift ◽  
Nuptial Gifts ◽  
Spider Species ◽  
Pisaura Mirabilis

Several not mutually exclusive functions have been ascribed to nuptial gifts across different taxa. Although the idea that a nuptial prey gift may protect the male from pre-copulatory sexual cannibalism is attractive, it has previously been considered of no importance based on indirect evidence and rejected by experimental tests. We reinvestigated whether nuptial gifts may function as a shield against female attacks during mating encounters in the spider Pisaura mirabilis and whether female hunger influences the likelihood of cannibalistic attacks. The results showed that pre-copulatory sexual cannibalism was enhanced when males courted without a gift and this was independent of female hunger. We propose that the nuptial gift trait has evolved partly as a counteradaptation to female aggression in this spider species.

scholarly journals Short-term changes in air humidity and water availability weakly constrain thermoregulation in a dry-skinned ectotherm

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0247514
Author(s):  
Jean-François Le Galliard ◽  
David Rozen-Rechels ◽  
Anjélica Lecomte ◽  
Clémence Demay ◽  
Andréaz Dupoué ◽  
...  
Keyword(s):  
Body Temperature ◽  
Water Availability ◽  
Behavioral Thermoregulation ◽  
Thermal Preference ◽  
Air Humidity ◽  
Short Term ◽  
Free Standing ◽  
Standing Water ◽  
Zootoca Vivipara ◽  
Thermal Preferences

Thermoregulation is critical for ectotherms as it allows them to maintain their body temperature close to an optimum for ecological performance. Thermoregulation includes a range of behaviors that aim at regulating body temperature within a range centered around the thermal preference. Thermal preference is typically measured in a thermal gradient in fully-hydrated and post-absorptive animals. Short-term effects of the hydric environment on thermal preferences in such set-ups have been rarely quantified in dry-skinned ectotherms, despite accumulating evidence that dehydration might trade-off with behavioral thermoregulation. Using experiments performed under controlled conditions in climatic chambers, we demonstrate that thermal preferences of a ground-dwelling, actively foraging lizard (Zootoca vivipara) are weakly decreased by a daily restriction in free-standing water availability (less than 0.5°C contrast). The influence of air humidity during the day on thermal preferences depends on time of the day and sex of the lizard, and is generally weaker than those of of free-standing water (less than 1°C contrast). This shows that short-term dehydration can influence, albeit weakly, thermal preferences under some circumstances in this species. Environmental humidity conditions are important methodological factors to consider in the analysis of thermal preferences.

Colonization of Marginal Host Plants by Seed Beetles (Coleoptera: Chrysomelidae): Effects of Geographic Source and Genetic Admixture

2020 ◽  
Vol 49 (4) ◽  
pp. 938-946
Author(s):  
Frank J Messina ◽  
Alexandra M Lish ◽  
Amy Springer ◽  
Zachariah Gompert
Keyword(s):  
Callosobruchus Maculatus ◽  
Larval Survival ◽  
Genetic Admixture ◽  
Parental Line ◽  
Long Distance ◽  
Asian Populations ◽  
Long Distance Transport ◽  
Novel Host ◽  
Colonization Success ◽  
Seed Beetles

Abstract The ability to adapt to a novel host plant may vary among insect populations with different genetic histories, and colonization of a marginal host may be facilitated by genetic admixture of disparate populations. We assembled populations of the seed beetle, Callosobruchus maculatus (F.), from four continents, and compared their ability to infest two hosts, lentil and pea. We also formed two cross-continent hybrids (Africa × N.A. and Africa × S.A.). In pre-selection assays, survival was only ~3% in lentil and ~40% in pea. For three replicate populations per line, colonization success on lentil was measured as cumulative exit holes after 75–175 d. On pea, we estimated the change in larval survival after five generations of selection. Females in all lines laid few eggs on lentil, and survival of F1 larvae was uniformly <5%. Subsequently, however, the lines diverged considerably in population growth. Performance on lentil was highest in the Africa × N.A. hybrid, which produced far more adults (mean > 11,000) than either parental line. At the other extreme, Asian populations on lentil appeared to have gone extinct. The Africa × N.A. line also exhibited the highest survival on pea, and again performed better than either parent line. However, no line displayed a rapid increase in survival on pea, as is sometimes observed on lentil. Our results demonstrate that geographic populations can vary substantially in their responses to the same novel resource. In addition, genetic admixtures (potentially caused by long-distance transport of infested seeds) may facilitate colonization of an initially poor host.

scholarly journals Kin but less than kind: within-group male relatedness does not increase female fitness in seed beetles

2019 ◽  
Vol 286 (1910) ◽  
pp. 20191664 ◽  
Author(s):  
Elena C. Berg ◽  
Martin I. Lind ◽  
Shannon Monahan ◽  
Sophie Bricout ◽  
Alexei A. Maklakov
Keyword(s):  
Sexual Conflict ◽  
Callosobruchus Maculatus ◽  
Lifetime Reproductive Success ◽  
Cognitive Error ◽  
Individual Fitness ◽  
Adaptive Mechanisms ◽  
Female Survival ◽  
Reproductive Part ◽  
Seed Beetles

Theory maintains within-group male relatedness can mediate sexual conflict by reducing male–male competition and collateral harm to females. We tested whether male relatedness can lessen female harm in the seed beetle Callosobruchus maculatus . Male relatedness did not influence female lifetime reproductive success or individual fitness across two different ecologically relevant scenarios of mating competition. However, male relatedness marginally improved female survival. Because male relatedness improved female survival in late life when C. maculatus females are no longer producing offspring, our results do not provide support for the role of within-group male relatedness in mediating sexual conflict. The fact that male relatedness improves the post-reproductive part of the female life cycle strongly suggests that the effect is non-adaptive. We discuss adaptive and non-adaptive mechanisms that could result in reduced female harm in this and previous studies, and suggest that cognitive error is a likely explanation.

scholarly journals ANALISIS PENGARUH BENTUK SERAMBI MASJID TERHADAP KENYAMANAN TERMAL ADAPTIF

2020 ◽  
Vol 4 (3) ◽  
pp. 261
Author(s):  
Abdul Qodir ◽  
Erni Setyowati ◽  
Suryono Suryono
Keyword(s):  
Thermal Comfort ◽  
Thermal Environment ◽  
Thermal Conditions ◽  
Temperature Range ◽  
Adaptive Thermal Comfort ◽  
Environment Variables ◽  
Average Condition ◽  
Radiant Temperature ◽  
Thermal Preferences ◽  
Neutral Conditions

This study examines the effect of the porch on the adaptive thermal comfort of mosques by taking 2 mosques that have different porch shapes with the specific purpose of obtaining data on the neutrality, acceptability and preferences of the mosque respondents' thermal conditions in the framework of developing adaptive thermal comfort standards for Indonesia. Measurement of physical environment variables is done by taking data on temperature, humidity, air velocity, and mean radiant temperature (MRT) at 2 mosques and at the same time the impression and thermal preference questionnaire data are taken, examination of clothing types and activities, and list of thermal environment controls to 40 respondents in each mosque. Data of thermal neutrality and thermal preferences were analyzed by regression analysis using SPSS 19 software, while thermal acceptance was analyzed based on the results of the questionnaire answers. The analysis showed that the neutrality value at Ulul Albab mosque was Tdb = 28.47 OC, ET * = 30.11 OC, SET * = 23.11 OC, TSENS = 1.17, DISC = -1.06, and PMV = -0.65, this data shows that the neutral condition desired by respondents is slightly below the average condition, while the neutrality in Nurul Ilmi mosque at Tdb = 30.27 OC, ET * = 31.65 OC, SET * = 29.05 OC, TSENS = 1.03, DISC = 1.68, and PMV = 1.22, this data also shows that the neutral conditions desired by respondents are slightly below average conditions. While the preference value at Ulul Albab mosque is Tdb = 22.25 OC, ET * = 28.62 OC, SET * = 24.24 OC, TSENS = 0.23, DISC = 0.23, and PMV = -0.60 and preference conditions at Nurul Ilmi mosque at Tdb = 29.11 OC, ET * = 31.17 OC, SET * = 28.50 OC, TSENS = 1.04, DISC = 1.45, and PMV = 1.03. As many as 92% of respondents in the Ulul Albab mosque can accept local thermal conditions in the temperature range of 27oC - 31oC. While 90% of respondents in the Nurul Ilmi mosque can accept local thermal conditions in the temperature range of 27oC-32oC. The results of the neutrality, acceptance and preference analysis show that the Ulul Albab mosque is better than the Nurul Ilmi mosque.

scholarly journals Potential effects of elevated temperature on seasonal movements in slipper lobsters, Scyllarides latus (Latreille, 1803), in the eastern Mediterranean

2020 ◽  
Author(s):  
JASON SETH GOLDSTEIN ◽  
EHUD SPANIER
Keyword(s):  
Behavioral Ecology ◽  
Thermal Environment ◽  
Eastern Mediterranean ◽  
Average Distance ◽  
Marine Reserve ◽  
Seasonal Movements ◽  
Spatial And Temporal Scales ◽  
Wide Range ◽  
Thermal Preferences ◽  
Insight Into

Temperature serves a predominant motivator for movement and activity over a wide range of mobile marine ectotherms. Water temperature modulates the movements of many lobster species, which can vary widely over spatial and temporal scales. Providing insight into the thermal preferences (and refuges) that some lobsters seek remains a key tenet to our understanding of the behavioral ecology of these animals. The Mediterranean slipper lobster (Scyllarides latus) shows seasonal movements throughout most of its range and is subject to a changing thermal environment. We examined the seasonal movements of S. latus within a small marine reserve (Rosh Hanikra Marine Reserve, RHR) off the coast of Israel and tested the hypothesis that S. latus engage in increased movements when subjected to temperatures outside their range. We conducted a field survey in the RHR and tagged lobsters (n = 81, carapace length, CLavg= 88.7 ± 4.6) to investigate their activity during their putative summer movement. In the lab, we exposed a separate set of lobsters (n = 10, CLavg= 83.1 ± 6.1) to the same thermal profiles as in the field and assayed their locomotion using activity wheels. Field results revealed that lobsters tagged in shallow waters moved to deeper, cooler waters (~ 30 m) over the course of 2-2.5 months traveling an average distance of 3.4 km (range = 1-5 km). Our lab results showed that S. latus are more active at higher temperatures, but moreover, revealed that warming water temperatures elicited markedly longer movements over a similar timeframe. Combined, these findings suggest that increasing water temperatures in the eastern Mediterranean (Levant) may affect lobster movements and could alter seasonal patterns of distribution as well.

scholarly journals Evolution of nuptial gifts and its coevolutionary dynamics with male-like persistence traits of females for multiple mating

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yoshitaka Kamimura ◽  
Kazunori Yoshizawa ◽  
Charles Lienhard ◽  
Rodrigo L. Ferreira ◽  
Jun Abe
Keyword(s):  
Multiple Mating ◽  
Sex Role ◽  
Critical Factor ◽  
Role Reversal ◽  
Female Competition ◽  
Mate Competition ◽  
Nuptial Gift ◽  
Nuptial Gifts ◽  
Mating Costs ◽  
Usage Patterns

Abstract Background Many male animals donate nutritive materials during courtship or mating to their female mates. Donation of large-sized gifts, though costly to prepare, can result in increased sperm transfer during mating and delayed remating of the females, resulting in higher paternity. Nuptial gifting sometimes causes severe female-female competition for obtaining gifts (i.e., sex-role reversal in mate competition) and selection on females to increase their mating rate, changing the intensity of sperm competition and the resultant paternity gains. We built a theoretical model to simulate such coevolutionary feedbacks between nuptial gift size (male trait) and propensity for multiple mating (female trait). Donation of nuptial gifts sometimes causes development of female persistence trait for gift acquisition. We also analyzed the causes and consequences of this type of traits, taking double receptacles for nutritious seminal gifts, which are known to occur in an insect group with a “female penis” (Neotrogla spp.), as an illustrative example. Results Our individual-based simulations demonstrated that female-female competition for male-derived nutrients always occur when the environment is oligotrophic and mating costs are low for females. However, a positive correlation between donated gift size and the resultant paternity gain was a requisite for the co-occurrence of large gifts and females’ competitive multiple mating for the gifts. When gift donation satisfied female demands and thus resulted in monandry, exaggeration of nuptial gift size also occurred under the assumption that the last male monopolizes paternity. The evolution of double slots for gift acquisition and digestion (female persistence trait) always occurred when males could not satisfy the demands of females for gifts. However, through coevolutionary reduction in male gift size, fixation of this trait in a population drastically reduced the average female fitness. Conclusion Sperm usage patterns, which have rarely been examined for animals with nuptial gifts, can be a critical factor for determining the extent of exaggeration in nuptial gifting. Sex-role reversals in mate competition, as a result of donation of nuptial gifts from males to females, can involve the evolution of male-like, persistent traits in females that reduce population productivity, as is the case with persistence traits in males.

scholarly journals Epigenetic Control of Temperature-Dependent Female Reproductive Life History Trade-Offs in Seed Beetles, Callosobruchus maculatus

2021 ◽  
Author(s):  
Beth Anne McCaw ◽  
Aoife M Leonard ◽  
Tyler J Stevenson ◽  
Lesley T Lancaster
Keyword(s):  
Dna Methylation ◽  
Life History ◽  
Callosobruchus Maculatus ◽  
Global Environmental Change ◽  
The Body ◽  
Temperature Dependent ◽  
Trade Offs ◽  
Reproductive Life ◽  
Seed Beetles ◽  
Reproductive Life History

Many species are threatened by climate change and must rapidly respond to survive changing environments. Epigenetic modifications, such as DNA methylation, can facilitate plastic responses by regulating gene expression in response to environmental cues. Understanding epigenetic responses is therefore essential for predicting species’ ability to rapidly adapt in the context of global environmental change. Here, we investigated the functional significance of DNA methylation on temperature-dependent life history in seed beetles, Callosobruchus maculatus. We assessed changes in DNA methyltransferase (Dnmt1 and Dnmt2) expression levels under ambient conditions and thermal stress, and reproductive performance following artificially-induced epimutation via 3-aminobenzamide (3AB) and Zebularine (Zeb), at a range of ambient and warmer temperatures over two generations. We found that Dnmt1 and Dnmt2 were greatly expressed in females, throughout the body, and exhibited temperature-dependence; in contrast, Dnmt expression was minimal in males. Epimutation led to shifts in female reproductive life history trade-off allocation, and differentially altered thermal optima of fecundity and offspring viability. This study revealed the optimal allocation strategy among these fitness components is temperature-dependent, and trade-offs become increasingly difficult to resolve epigenetically under more extreme warming. Results suggest that epigenetic mechanisms are strongly implicated in, and perhaps limiting of, invertebrate life history responses to temperature change. Further investigation will reveal targeted DNA methylation patterns and specific loci associated with temperature-dependent life history trade-offs in seed beetles and other invertebrates.

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