Lack of evidence for pheromones in lemurs.

As chemicals that elicit unlearned, functionally specialized, and species-specific responses [1] or 'stereotyped behavior' [2], pheromones differ from mammalian scent signatures that comprise complex, variable mixtures, convey multiple messages via learned chemical combinations, and elicit generalized responses [1]. Studying ring-tailed lemur (Lemur catta) behavior and semiochemistry, a recent study by Shirasu, Ito et al. [2] claimed to have identified "the first sex pheromones in primates.

Costs of injury for scent signalling in a strepsirrhine primate.

Honesty is crucial in animal communication when signallers are conveying information about their condition. Condition dependence implies a cost to signal production; yet, evidence of such cost is scarce. We examined the effects of naturally occurring injury on the quality and salience of olfactory signals in ring-tailed lemurs (Lemur catta).

The "secret" in secretions: methodological considerations in deciphering primate olfactory communication.

Olfactory communication in primates is gaining recognition; however, studies on the production and perception of primate scent signals are still scant. In general, there are five tasks to be accomplished when deciphering the chemical signals contained in excretions and secretions: (1) obtaining the appropriate samples; (2) extracting the target organic compounds from the biological matrix; (3) separating the extracted compounds from one another (by gas chromatography, GC or liquid chromatography, LC); (4) identifying the compounds (by mass spectrometry, MS and associated procedures); and (5) revealing biologically meaningful patterns in the data. Ultimately, because some of the compounds identified in odorants may not be relevant, associated steps in understanding signal function involve verifying the perception or biological activity of putative semiochemicals via (6) behavioral bioassays or (7) receptor response studies.

Smelling wrong: hormonal contraception in lemurs alters critical female odour cues.

Animals, including humans, use olfaction to assess potential social and sexual partners. Although hormones modulate olfactory cues, we know little about whether contraception affects semiochemical signals and, ultimately, mate choice. We examined the effects of a common contraceptive, medroxyprogesterone acetate (MPA), on the olfactory cues of female ring-tailed lemurs (Lemur catta), and the behavioural response these cues generated in male conspecifics.

Decoding an olfactory mechanism of kin recognition and inbreeding avoidance in a primate.

Background: Like other vertebrates, primates recognize their relatives, primarily to minimize inbreeding, but also to facilitate nepotism. Although associative, social learning is typically credited for discrimination of familiar kin, discrimination of unfamiliar kin remains unexplained. As sex-biased dispersal in long-lived species cannot consistently prevent encounters between unfamiliar kin, inbreeding remains a threat and mechanisms to avoid it beg explanation.

Smelling right: the scent of male lemurs advertises genetic quality and relatedness.

Sexual selection theory predicts that competitors or potential mates signal their quality or relatedness to conspecifics. Researchers have focused on visual or auditory modes of signal transmission; however, the importance of olfactory indicators is gaining recognition. Using a primate model and a new integrative analytical approach, we provide the first evidence relating male olfactory cues to individual genome-wide heterozygosity and to the genetic distance between individuals.

Integrative use of spatial, genetic, and demographic analyses for investigating genetic connectivity between migratory, montane, and sedentary caribou herds.

Genetic differentiation is generally assumed to be low in highly mobile species, but this simplistic view may obscure the complex conditions and mechanisms allowing genetic exchanges between specific populations. Here, we combined data from satellite-tracked migratory caribou (Rangifer tarandus), microsatellite markers, and demographic simulations to investigate gene flow mechanisms between seven caribou herds of eastern Canada. Our study included one montane, two migratory, and four sedentary herds.

Lineage origin and expansion of a Neotropical migrant songbird after recent glaciation events.

Birds of the Northern Hemisphere often harbour the genetic signature of postglaciation expansion but analyses identifying the location of refugia and the directionality of expansions are rare. Here we explore the evolutionary history of yellow warbler lineages, focusing on how these lineages recolonized their current range. We genotyped samples from 696 yellow warblers via direct sequencing of a 333-bp control region I mitochondrial DNA fragment or lineage-specific genotyping.