Vomeronasal organ volume increases with body size and is dissociated with the loss of a visual signal in Sceloporus lizards.

Many organisms communicate using signals in different sensory modalities (multicomponent or multimodal). When one signal or component is lost over evolutionary time, it may be indicative of changes in other characteristics of the signalling system, including the sensory organs used to perceive and process signals. Sceloporus lizards predominantly use chemical and visual signals to communicate, yet some species have lost the ancestral ventral colour patch used in male-male agonistic interactions and exhibit increased chemosensory behaviour.

Ecological factors shaping ectoparasite communities on heteromyid rodents at Médanos de Samalayuca.

Rodent ectoparasites are vectors for important pathogens of wildlife, domestic animals, and even zoonosis. Nevertheless, distribution patterns of ectoparasites are not fully understood; habitat, season, and host species are important predictors of distribution and prevalence. Heteromyid rodents are considered important reservoirs of diseases, given the presence of different ectoparasites and pathogens in them, and they offer the opportunity to learn about the ecology of parasites.

Molecular Detection and Characterization of Isolates from Three Geographic Regions in Mexico: A Retrospective Study.

Canine monocytic ehrlichiosis (CME) is the most common tick-borne disease affecting domestic dogs and other wild canids. It has a worldwide distribution and is associated with the presence of the brown dog tick. Few studies have been conducted in Mexico to identify and characterize genetic variability.

The recombination landscapes of spiny lizards (genus Sceloporus).

Despite playing a critical role in evolutionary processes and outcomes, relatively little is known about rates of recombination in the vast majority of species, including squamate reptiles-the second largest order of extant vertebrates, many species of which serve as important model organisms in evolutionary and ecological studies. This paucity of data has resulted in limited resolution on questions related to the causes and consequences of rate variation between species and populations, the determinants of within-genome rate variation, as well as the general tempo of recombination rate evolution on this branch of the tree of life. In order to address these questions, it is thus necessary to begin broadening our phylogenetic sampling.

Molecular Detection of Tick-Borne Pathogens in American Bison () at El Uno Ecological Reserve, Janos, Chihuahua, Mexico.

American bison () is listed as near-threatened and in danger of extinction in Mexico. Recent studies have demonstrated the presence of several emerging pathogens at the Janos Biosphere Reserve (JBR), inhabited by one wild herd of American bison. Blood samples were collected from 26 American bison in the JBR.

Information out of the blue: phenotypic correlates of abdominal color patches in Sceloporus lizards.

Colorful ornaments are important visual signals for animal communication that can provide critical information about the quality of the signaler. In this study, we focused on different color characteristics of the abdominal patches of males of six lizard species from the genus Sceloporus. We addressed three main objectives.

Volatile fatty acid and aldehyde abundances evolve with behavior and habitat temperature in lizards.

Animal signals evolve by striking a balance between the need to convey information through particular habitats and the limitations of what types of signals can most easily be produced and perceived. Here, we present new results from field measures of undisturbed behavior and biochemical analyses of scent marks from 12 species of lizards to explore whether evolutionary changes in chemical composition are better predicted by measures of species behavior, particularly those associated with visual displays, chemoreception, and locomotion, or by measures of habitat climate (precipitation and temperature). We found that more active lizard species used fewer compounds in their volatile scent marks, perhaps conveying less specific information about individual and species identity.

First report of Siphonaptera parasites in Canis latrans in the Flora and Fauna Protection Area, Médanos de Samalayuca Chihuahua, Mexico.

Siphonaptera are hematophage parasite vectors of both human and animal diseases. We aimed to identify ectoparasites parasitizing a coyote population (Canis latrans) in the northwest region of the Flora and Fauna Protection Area Médanos de Samalayuca, Chihuahua, Mexico. We captured 21 coyotes (15 males and 6 females) during the summer and winter of 2018.

First report of Libyostrongylus douglassii (Strongylida: Trichostrongylidae) in ostriches (Struthio camelus) from Mexico.

Nematodes of the Libyostrongylus genus are hematophagous parasites found under the ostrich's proventriculus membrane: they are frequent and can cause 50% of mortality in chicks and occasionally death in adults. With the aim of determining the presence of the Libyostrongylus genus in two private collections, one located in Ayapango, State of Mexico and the other in Amacuzac, Morelos, a total of 27 fecal samples were collected between August and December of 2016. Samples were analyzed using the flotation technique.

Losing the trait without losing the signal: Evolutionary shifts in communicative colour signalling.

Colour signalling traits are often lost over evolutionary time, perhaps because they increase vulnerability to visual predators or lose relevance in terms of sexual selection. Here, we used spectrometric and phylogenetic comparative analyses to ask whether four independent losses of a sexually selected blue patch are spectrally similar, and whether these losses equate to a decrease in conspicuousness or to loss of a signal. We found that patches were lost in two distinct ways: either increasing reflectance primarily at very long or at very short wavelengths, and that species with additional colour elements (UV, green and pink) may be evolutionary intermediates.

Shaping communicative colour signals over evolutionary time.

Many evolutionary forces can shape the evolution of communicative signals, and the long-term impact of each force may depend on relative timing and magnitude. We use a phylogenetic analysis to infer the history of blue belly patches of lizards, and a detailed spectrophotometric analysis of four species to explore the specific forces shaping evolutionary change. We find that the ancestor of had blue patches.

Evolutionary Interactions Between Visual and Chemical Signals: Chemosignals Compensate for the Loss of a Visual Signal in Male Sceloporus Lizards.

Animals rely on multimodal signals to obtain information from conspecifics through alternative sensory systems, and the evolutionary loss of a signal in one modality may lead to compensation through increased use of signals in an alternative modality. We investigated associations between chemical signaling and evolutionary loss of abdominal color patches in males of four species (two plain-bellied and two colorful-bellied) of Sceloporus lizards. We conducted field trials to compare behavioral responses of male lizards to swabs with femoral gland (FG) secretions from conspecific males and control swabs (clean paper).

Evolving from static to dynamic signals: evolutionary compensation between two communicative signals.

Signals that convey related information may impose selection on each other, creating evolutionary links between different components of the communicative repertoire. Here, we ask about the consequences of the evolutionary loss of one signal (a colour patch) on another (a motion display) in lizards. We present data on male lizards of four species: two pairs of sister taxa representing two independent evolutionary losses of the static colour patch ( and ; and ).