Overcoming the congenitally disadvantageous mutation through adaptation to environmental UV exposure in land snails
Biol Lett. 2023 Nov;19(11):20230356. doi: 10.1098/rsbl.2023.0356. Epub 2023 Nov 22.ABSTRACTCongenital fitness-disadvantageous mutations are not maintained in the population; they are purged from the population through processes such as purifying selection. However, these mutations could persist in the population as polymorphisms when it is advantageous for the individuals carrying them in adapting to a specific external environment. We tested this hypothesis using the dimorphic land snail Euhadra peliomphala simodae in Japan; these snails have dark or bright coloured shells. The survival rate of dark snails at hatching was...
Source: Biology Letters - November 22, 2023 Category: Biology Authors: Shun Ito Satoshi Chiba Junji Konuma Source Type: research
Embryonic exposure to artificial light at night impairs learning abilities and their covariance with behavioural traits in teleost fish
Biol Lett. 2023 Nov;19(11):20230436. doi: 10.1098/rsbl.2023.0436. Epub 2023 Nov 22.ABSTRACTThe natural light cycle has profound effects on animals' cognitive systems. Its alteration owing to human activities, such as artificial light at night (ALAN), affects the biodiversity of mammalian and avian species by impairing their cognitive functions. The impact of ALAN on cognition, however, has not been investigated in aquatic species, in spite of the common occurrence of this pollution along water bodies. We exposed eggs of a teleost fish (the zebrafish Danio rerio) to ALAN and, upon hatching, we measured larvae' cognitive abi...
Source: Biology Letters - November 22, 2023 Category: Biology Authors: Tyrone Lucon-Xiccato Gaia De Russi Stefano Cannicci Elena Maggi Cristiano Bertolucci Source Type: research
Small increases in ambient temperature reduce offspring body mass in an equatorial mammal
Biol Lett. 2023 Nov;19(11):20230328. doi: 10.1098/rsbl.2023.0328. Epub 2023 Nov 22.ABSTRACTHuman-induced climate change is leading to temperature rises, along with increases in the frequency and intensity of heatwaves. Many animals respond to high temperatures through behavioural thermoregulation, for example by resting in the shade, but this may impose opportunity costs by reducing foraging time (therefore energy supply), and so may be most effective when food is abundant. However, the heat dissipation limit (HDL) theory proposes that even when energy supply is plentiful, high temperatures can still have negative effects....
Source: Biology Letters - November 22, 2023 Category: Biology Authors: Monil Khera Kevin Arbuckle Francis Mwanguhya Solomon Kyabulima Kenneth Mwesige Robert Businge Jonathan D Blount Michael A Cant Hazel J Nichols Source Type: research
Sexual selection for extreme physical performance in a polygynous bird is associated with exceptional sex differences in oxygen carrying capacity
We examined the oxygen carrying capacity of pectoral sandpipers, measured as the volume percentage of red blood cells in blood (haematocrit, Hct). We found a remarkable sex difference in Hct levels, with males having much higher values (58.9 ± 3.8 s.d.) than females (49.8 ± 5.3 s.d.). While Hct values of male pectoral sandpipers are notable for being among the highest recorded in birds, the sex difference we report is unprecedented and more than double that of any previously described. We also show that Hct values declined after arrival to the breeding grounds in females, but not in males, suggesting that males maintain ...
Source: Biology Letters - November 22, 2023 Category: Biology Authors: Peter Santema Luke Eberhart-Hertel Mihai Valcu Bart Kempenaers Source Type: research
Paternal environment effects are driven by female reproductive fluid but not sperm age in an external fertilizer
Biol Lett. 2023 Nov;19(11):20230368. doi: 10.1098/rsbl.2023.0368. Epub 2023 Nov 22.ABSTRACTSperm ageing after ejaculation can generate paternal environment effects that impact offspring fitness. In many species, female reproductive fluids (FRFs), i.e. ancillary fluids released by eggs or within the female reproductive tract, may protect sperm from ageing and can additionally interact with sperm to influence offspring viability. This raises the intriguing prospect that FRFs may alleviate paternal effects associated with sperm ageing. Here, we test this novel hypothesis using the broadcast spawning mussel, Mytilus galloprovi...
Source: Biology Letters - November 22, 2023 Category: Biology Authors: Jessica H Hadlow Rowan A Lymbery Jonathan P Evans Source Type: research
Birds are better at regulating heat loss through their legs than their bills: implications for body shape evolution in response to climate
Biol Lett. 2023 Nov;19(11):20230373. doi: 10.1098/rsbl.2023.0373. Epub 2023 Nov 22.ABSTRACTEndotherms use their appendages-such as legs, tails, ears and bills-for thermoregulation by controlling blood flow to near-surface blood vessels, conserving heat when it is cold, and dissipating heat in hot conditions. Larger appendages allow greater heat dissipation, and appendage sizes vary latitudinally according to Allen's rule. However, little is known about the relative importance of different appendages for thermoregulation. We investigate physiological control of heat loss via bird bills and legs using infrared thermography o...
Source: Biology Letters - November 22, 2023 Category: Biology Authors: Alexandra McQueen Ryan Barnaby Matthew R E Symonds Glenn J Tattersall Source Type: research
Foraging mode constrains the evolution of cephalic horns in lizards and snakes
Biol Lett. 2023 Nov;19(11):20230395. doi: 10.1098/rsbl.2023.0395. Epub 2023 Nov 22.ABSTRACTA phylogenetically diverse minority of snake and lizard species exhibit rostral and ocular appendages that substantially modify the shape of their heads. These cephalic horns have evolved multiple times in diverse squamate lineages, enabling comparative tests of hypotheses on the benefits and costs of these distinctive traits. Here, we demonstrate correlated evolution between the occurrence of horns and foraging mode. We argue that although horns may be beneficial for various functions (e.g. camouflage, defence) in animals that move ...
Source: Biology Letters - November 22, 2023 Category: Biology Authors: Federico Banfi Shai Meiri Richard Shine Raoul Van Damme Simon Baeckens Source Type: research
The efficiency of varying methods and degrees of time compensation for the solar azimuth
Biol Lett. 2023 Nov;19(11):20230355. doi: 10.1098/rsbl.2023.0355. Epub 2023 Nov 22.ABSTRACTDaytime migrants are known to orientate using the position of the sun, compensating for its changing position throughout the day with a 'time-compensated sun compass'. This compass has been demonstrated in many migratory species, with various degrees of accuracy for the actual movement of the sun. Here, we present a model for differing levels of compensation for the solar ephemeris that shows that a high degree of efficiency, in terms of distance travelled, can be achieved without full time compensation. In our model, compensating fo...
Source: Biology Letters - November 22, 2023 Category: Biology Authors: Richard Massy Karl R Wotton Source Type: research
Overcoming the congenitally disadvantageous mutation through adaptation to environmental UV exposure in land snails
Biol Lett. 2023 Nov;19(11):20230356. doi: 10.1098/rsbl.2023.0356. Epub 2023 Nov 22.ABSTRACTCongenital fitness-disadvantageous mutations are not maintained in the population; they are purged from the population through processes such as purifying selection. However, these mutations could persist in the population as polymorphisms when it is advantageous for the individuals carrying them in adapting to a specific external environment. We tested this hypothesis using the dimorphic land snail Euhadra peliomphala simodae in Japan; these snails have dark or bright coloured shells. The survival rate of dark snails at hatching was...
Source: Biology Letters - November 22, 2023 Category: Biology Authors: Shun Ito Satoshi Chiba Junji Konuma Source Type: research
Embryonic exposure to artificial light at night impairs learning abilities and their covariance with behavioural traits in teleost fish
Biol Lett. 2023 Nov;19(11):20230436. doi: 10.1098/rsbl.2023.0436. Epub 2023 Nov 22.ABSTRACTThe natural light cycle has profound effects on animals' cognitive systems. Its alteration owing to human activities, such as artificial light at night (ALAN), affects the biodiversity of mammalian and avian species by impairing their cognitive functions. The impact of ALAN on cognition, however, has not been investigated in aquatic species, in spite of the common occurrence of this pollution along water bodies. We exposed eggs of a teleost fish (the zebrafish Danio rerio) to ALAN and, upon hatching, we measured larvae' cognitive abi...
Source: Biology Letters - November 22, 2023 Category: Biology Authors: Tyrone Lucon-Xiccato Gaia De Russi Stefano Cannicci Elena Maggi Cristiano Bertolucci Source Type: research
Small increases in ambient temperature reduce offspring body mass in an equatorial mammal
Biol Lett. 2023 Nov;19(11):20230328. doi: 10.1098/rsbl.2023.0328. Epub 2023 Nov 22.ABSTRACTHuman-induced climate change is leading to temperature rises, along with increases in the frequency and intensity of heatwaves. Many animals respond to high temperatures through behavioural thermoregulation, for example by resting in the shade, but this may impose opportunity costs by reducing foraging time (therefore energy supply), and so may be most effective when food is abundant. However, the heat dissipation limit (HDL) theory proposes that even when energy supply is plentiful, high temperatures can still have negative effects....
Source: Biology Letters - November 22, 2023 Category: Biology Authors: Monil Khera Kevin Arbuckle Francis Mwanguhya Solomon Kyabulima Kenneth Mwesige Robert Businge Jonathan D Blount Michael A Cant Hazel J Nichols Source Type: research
Sexual selection for extreme physical performance in a polygynous bird is associated with exceptional sex differences in oxygen carrying capacity
We examined the oxygen carrying capacity of pectoral sandpipers, measured as the volume percentage of red blood cells in blood (haematocrit, Hct). We found a remarkable sex difference in Hct levels, with males having much higher values (58.9 ± 3.8 s.d.) than females (49.8 ± 5.3 s.d.). While Hct values of male pectoral sandpipers are notable for being among the highest recorded in birds, the sex difference we report is unprecedented and more than double that of any previously described. We also show that Hct values declined after arrival to the breeding grounds in females, but not in males, suggesting that males maintain ...
Source: Biology Letters - November 22, 2023 Category: Biology Authors: Peter Santema Luke Eberhart-Hertel Mihai Valcu Bart Kempenaers Source Type: research
Paternal environment effects are driven by female reproductive fluid but not sperm age in an external fertilizer
Biol Lett. 2023 Nov;19(11):20230368. doi: 10.1098/rsbl.2023.0368. Epub 2023 Nov 22.ABSTRACTSperm ageing after ejaculation can generate paternal environment effects that impact offspring fitness. In many species, female reproductive fluids (FRFs), i.e. ancillary fluids released by eggs or within the female reproductive tract, may protect sperm from ageing and can additionally interact with sperm to influence offspring viability. This raises the intriguing prospect that FRFs may alleviate paternal effects associated with sperm ageing. Here, we test this novel hypothesis using the broadcast spawning mussel, Mytilus galloprovi...
Source: Biology Letters - November 22, 2023 Category: Biology Authors: Jessica H Hadlow Rowan A Lymbery Jonathan P Evans Source Type: research
Birds are better at regulating heat loss through their legs than their bills: implications for body shape evolution in response to climate
Biol Lett. 2023 Nov;19(11):20230373. doi: 10.1098/rsbl.2023.0373. Epub 2023 Nov 22.ABSTRACTEndotherms use their appendages-such as legs, tails, ears and bills-for thermoregulation by controlling blood flow to near-surface blood vessels, conserving heat when it is cold, and dissipating heat in hot conditions. Larger appendages allow greater heat dissipation, and appendage sizes vary latitudinally according to Allen's rule. However, little is known about the relative importance of different appendages for thermoregulation. We investigate physiological control of heat loss via bird bills and legs using infrared thermography o...
Source: Biology Letters - November 22, 2023 Category: Biology Authors: Alexandra McQueen Ryan Barnaby Matthew R E Symonds Glenn J Tattersall Source Type: research
Foraging mode constrains the evolution of cephalic horns in lizards and snakes
Biol Lett. 2023 Nov;19(11):20230395. doi: 10.1098/rsbl.2023.0395. Epub 2023 Nov 22.ABSTRACTA phylogenetically diverse minority of snake and lizard species exhibit rostral and ocular appendages that substantially modify the shape of their heads. These cephalic horns have evolved multiple times in diverse squamate lineages, enabling comparative tests of hypotheses on the benefits and costs of these distinctive traits. Here, we demonstrate correlated evolution between the occurrence of horns and foraging mode. We argue that although horns may be beneficial for various functions (e.g. camouflage, defence) in animals that move ...
Source: Biology Letters - November 22, 2023 Category: Biology Authors: Federico Banfi Shai Meiri Richard Shine Raoul Van Damme Simon Baeckens Source Type: research
