Geology topics

Herve Mulard

Publications and source records attributed to Herve Mulard.

6 recordsLinked to original sources

USGS2011

Semiochemical compounds of preen secretion reflect genetic make-up in a seabird species

Several vertebrates choose their mate according to genetic heterozygosity and relatedness, and use odour cues to assess their conspecifics' genetic make-up. In birds, although several species (including the black-legged kittiwake) exhibit non-random mating according to genetic traits, the cues used to assess genetic characteristics remain unknown. The importance of olfaction in birds' social behaviour is gaining attention among researchers, and it has been suggested that, as in other vertebrates, bird body scent may convey information about genetic traits. Here, we combined gas chromatography data and genetic analyses at microsatellite loci to test whether semiochemical messages in preen secretion of kittiwakes carried information about genetic heterozygosity and relatedness. Semiochemical profile was correlated with heterozygosity in males and females, while semiochemical distance was correlated with genetic distance only in male–male dyads. Our study is the first to demonstrate a link between odour and genetics in birds, which sets the stage for the existence of sophisticated odour-based mechanisms of mate choice also in birds.

Proceedings of the Royal Society B: Biological Sci↗

USGS2010

Sexually transmitted bacteria affect female cloacal assemblages in a wild bird

Sexual transmission is an important mode of disease propagation, yet its mechanisms remain largely unknown in wild populations. Birds comprise an important model for studying sexually transmitted microbes because their cloaca provides a potential for both gastrointestinal pathogens and endosymbionts to become incorporated into ejaculates. We experimentally demonstrate in a wild population of kittiwakes ( Rissa tridactyla ) that bacteria are transmitted during copulation and affect the composition and diversity of female bacterial communities. We used an anti-insemination device attached to males in combination with a molecular technique (automated ribosomal intergenic spacer analysis) that describes bacterial communities. After inseminations were experimentally blocked, the cloacal communities of mates became increasingly dissimilar. Moreover, female cloacal diversity decreased and the extinction of mate-shared bacteria increased, indicating that female cloacal assemblages revert to their pre-copulatory state and that the cloaca comprises a resilient microbial ecosystem.

Ecology Letters↗

USGS2010

Sustained increase in food supplies reduces broodmate aggression in black-legged kittiwakes

The amount of food ingested by chicks has often been suggested as being the main proximate factor controlling broodmate aggression in facultatively siblicidal species. Although several experiments have demonstrated that short-term food deprivation causes a temporary increase in aggression, no study has, to our knowledge, experimentally manipulated overall food supplies and considered long-term effects on chick behaviour and life history traits. We provided supplemental food to breeding pairs of black-legged kittiwakes, Rissa tridactyla , over an entire breeding season and compared the aggressive behaviour of their chicks with that of chicks of control pairs. Control A-chicks (first to hatch) showed more frequent and intense aggression than their experimental counterparts. Furthermore, the more A-chicks begged and the lower their growth rate the more aggressive they were. The consequences of increased aggression for B-chicks (second to hatch) were lower begging rate, lower growth rate and lower survival. We thus provide evidence that a sustained increase in food availability affects broodmate aggression and chick survival at the nest and we discuss the various proximate and ultimate causes involved in the evolution of broodmate aggression.

Alaska↗

USGS2009

Evidence that pairing with genetically similar mates is maladaptive in a monogamous bird

Background Evidence of multiple genetic criteria of mate choice is accumulating in numerous taxa. In many species, females have been shown to pair with genetically dissimilar mates or with extra-pair partners that are more genetically compatible than their social mates, thereby increasing their offsprings' heterozygosity which often correlates with offspring fitness. While most studies have focused on genetically promiscuous species, few studies have addressed genetically monogamous species, in which mate choice tends to be mutual. Results Here, we used microsatellite markers to assess individual global heterozygosity and genetic similarity of pairs in a socially and genetically monogamous seabird, the black-legged kittiwake Rissa tridactyla . We found that pairs were more genetically dissimilar than expected by chance. We also identified fitness costs of breeding with genetically similar partners: (i) genetic similarity of pairs was negatively correlated with the number of chicks hatched, and (ii) offspring heterozygosity was positively correlated with growth rate and survival. Conclusion These findings provide evidence that breeders in a genetically monogamous species may avoid the fitness costs of reproducing with a genetically similar mate. In such species that lack the opportunity to obtain extra-pair fertilizations, mate choice may therefore be under high selective pressure.

Alaska↗

USGS2009

Can kittiwakes smell? Experimental evidence in a larid species

Birds have long been thought to have a poor sense of smell, although they have the proper anatomical and neurological structures for detecting olfactory cues ( Roper 1999 ). However, in the past decade several bird species have been shown to use smell in various contexts, such as foraging ( Nevitt et al. 1995 ), navigation ( Wallraff 2004 ), selection of nest materials ( Petit et al. 2002 , Gwinner & Berger 2008 ), nest location ( Bonadonna & Bretagnolle 2002 ), predator avoidance ( Amo et al. 2008 , Roth et al. 2008 ) and recognition of conspecifics ( Hagelin et al. 2003 ) or mates ( Bonadonna & Nevitt 2004 , for reviews see Roper 1999 , Hagelin & Jones 2007 , Nevitt 2008 ). The evidence, however, mainly concerns the Procellariiformes (petrels, shearwaters and albatrosses), a group that has long been suspected of using olfaction because of their strong body odour, highly developed olfactory bulb, nocturnal habits and burrow‐nesting ( Nevitt & Bonadonna 2005 , Nevitt 2008 ). Evidence of olfactory ability is scarce in other avian taxa. Exceptions include, for instance, Turkey Vulture Cathartes aura ( Smith & Paselk 1986 ), Brown Kiwi Apteryx australis ( Wenzel 1968 ), Homing Pigeon Columba livia ( Wallraff 2004 ), Blue Tit Cyanistes caeruleus ( Petit et al. 2002 , Amo et al. 2008 ), Domestic Fowl Gallus domesticus ( McKeegan et al. 2005 ), Kakapo Strigops habroptilus ( Hagelin 2004 ), Yellow‐backed Chattering Lory Lorius garrulus flavopalliatus ( Roper 2003 ), African Penguin Spheniscus demersus ( Cunningham et al. 2008 ) and Crested Auklets Aethia cristatella ( Hagelin et al. 2003 ). The Laridae, including Black‐legged Kittiwakes Rissa tridactyla , are diurnal, have relatively small olfactory bulbs ( Bang & Cobb 1968 ) and do not appear to use olfaction to locate food ( Frings et al. 1955 , Lequette et al. 1989 , Verheyden & Jouventin 1994 ). Kittiwakes use vocal cues in mate and parent/offspring recognition ( Wooller 1978 , Mulard & Danchin 2008 ), suggesting that olfaction may be at best secondary in those contexts. However, mates commonly allopreen, potentially exposing them to their mate’s chemical compounds. Moreover, the relative size of the olfactory bulb may be a poor predictor of olfactory abilities ( Hagelin 2004 , Mennerat et al. 2005 ). The aim of this experimental study was to assess whether Black‐legged Kittiwakes are able to detect odours added to the nest.

Alaska↗

USGS2008

Multiple deleterious effects of experimentally aged sperm in a monogamous bird

Sperm aging is known to be detrimental to reproductive performance. However, this apparently general phenomenon has seldom been studied in an evolutionary context. The negative impact of sperm aging on parental fitness should constitute a strong selective pressure for adaptations to avoid its effects. We studied the impact of sperm aging on black-legged kittiwakes ( Rissa tridactyla ), a monogamous seabird. Kittiwakes comprise a model system because ( i ) of evidence that females eject their mates' sperm to prevent fertilization by sperm that would be old and degraded by the time of fertilization and result in reduced reproductive performance and ( ii ) the lack of extra-pair fertilization in this species makes cryptic female choice an unlikely explanation of postcopulatory sperm ejection by females. We experimentally manipulated the age of the sperm fertilizing kittiwake eggs by fitting males with anti-insemination rings for variable periods of time preceding egg-laying. We found evidence that sperm aging negatively affected four sequential stages of reproduction: fertilization potential, rate of embryonic development, embryonic mortality, and chick condition at hatching. These results may be produced by a continuum of a single process of sperm aging that differentially affects various aspects of development, depending on the degree of damage incurred to the spermatozoa. The marked impact of sperm age on female fitness may thus drive postcopulatory sperm ejection by females. These results provide experimental evidence of deleterious effects of sperm aging on a nondomestic vertebrate, underlining its taxonomic generality and its potential to select for a wide array of adaptations.

PNAS↗