Frugivorous and granivorous vertebrates often discriminate against seeds and fruits infested by insects (Sallabanks & Courtney 1992). Insects may actively render seed or fruit unpalatable or unusable to vertebrates as a strategy to maximize the amount of food available to themselves (Janzen 1977). Nevertheless, vertebrates sometimes do not differentiate between sound and infested seeds or fruits (Dixon et al. 1997, Weckerly et al. 1989), or even prefer insect-infested seeds and fruits to sound ones (Sallabanks & Courtney 1992, Semel & Andersen 1988, Steele et al. 1996, Valburg 1992). Possible reasons for vertebrates to prefer infested seeds include: (1) seeds with larvae having a higher nutritional value than sound ones, because larvae synthesize fat and/or proteins (Sallabanks & Courtney 1992, Valburg 1992) or other nutrients such as vitamins (Havera & Smith 1979, Semel & Andersen 1988, Steele et al. 1996); (2) seeds with larvae tasting better than sound seeds (Borowicz 1988); and (3) seeds with larvae may be more easily opened and consumed than sound seeds (Borowicz 1988).

Parasites and their hosts use different strategies to overcome the defenses of the other, often resulting in an evolutionary arms race. Limited animal studies have explored the differential responses of hosts when challenged by differential parasite loads and different developmental stages of a parasite. The fungus-growing ant Trachymyrmex sp. 10 employs three different hygienic strategies to control fungal pathogens: Grooming the antibiotic-producing metapleural glands (MGs) and planting or weeding their mutualistic fungal crop. By inoculating Trachymyrmex colonies with different parasite concentrations (Metarhizium) or stages (germinated conidia or ungermianted conidia of Metarhizium and Escovopsis), we tested whether ants modulate and change hygienic strategies depending on the nature of the parasite challenge. There was no effect of the concentration of parasite on the frequencies of the defensive behaviors, indicating that the ants did not change defensive strategy according to the level of threat. However, when challenged with conidia of Escovopsis sp. and Metarhizium brunneum that were germinated or not-germinated, the ants adjusted their thygienic behavior to fungal planting and MG grooming behaviors using strategies depending on the conidia germination status. Our study suggests that fungus-growing ants can adjust the use of hygienic strategies based on the nature of the parasites.

Leaf-cutter ant nests attract a wide variety of guests and parasites due to considerable food resources, substrate and shelter available within nests. Limited information is known about their taxonomy, bionomics, and natural history, including interactions with the ants, and degree of host specificity of these symbionts. Here we describe two new species of Szelenyiopria Fabritius, 1974 (Diapriidae, Diapriinae, Diapriini) wasps which are koinobiont endoparasitoids of the larvae of a leaf-cutter ant, Acromyrmex coronatus (Fabricius, 1804) (Myrmicinae, Attini) in Chiriquí, Panama. For both new Szelenyiopria species, S. fortunensis Araúz & Fernández-Marín, sp. nov. and S. chiriquiensis Araúz & Fernández-Marín, sp. nov., we provide information on parasite–host interactions. The most abundant and frequent parasitoid type was solitary, while gregarious parasitoidism, where two or more wasps emerged from a single ant larva, was associated with certain times of the year. We provide an updated key to females of all species of Szelenyiopria, their geographic distribution, and host–parasite interactions. Szelenyiopria previously had been identified as parasitoids of several ant genera including some Acromyrmex species, but our data indicate that some species of Szelenyiopria may be specialized on A. coronatus ants. Rates of parasitism suggest that the wasps have a negative effect on colonies and populations of the ants.

Predators exert negative effects on prey, besides the act of killing, generating behavioral and physiological costs, a concept known as the ecology of fear. Studies in scatter-hoarding rodents in temperate zones suggests that prey use habitat structure to perceive predation risk. Less is known about how tropical forest rodents perceive predation risk. Here, we investigated whether the Central American agouti perceive predation risk by ocelots through olfactory cues and whether it influences the foraging behavior for Attalea butyracea seeds, one of its main food sources. By monitoring tagged seeds, we found that seed dispersal and pilferage was lower in sites with high density of ocelots, in line with the predictions of ecology of fear proposing that scared animals eat less. We also found that pilferage rates in high ocelot density sites seem to be lower during the rainy—transition period but not during dry season when food availability is generally low. However, we did not find evidence that agoutis adjust their cache spacing behavior in response to ocelot density. In an additional experiment to corroborate that agoutis’ responses were caused by ocelots’ cues, we found lower dispersal rates for seeds placed next to samples of urine and feces of ocelots as compared to controls, during the first seven days. Moreover, agoutis spent less time handling the seeds with ocelots’ cues. Here, we discuss potential cascading effects linked to the behavior of agoutis towards predation risk.

Coloration anomalies are widespread across the animal kingdom; however, they pass underreported for some taxa or are extremely rare, like in the case of mammals. Three of those anomalies are albinism, leucism, and erythrism, each of which generates atypical colorations in white with white spots and reddish-brown, respectively. Here, we report five cases of coloration anomalies in mammals from Panama: 1) albinism in the Derby’s woolly opossum (Caluromys derbianus Waterhouse, 1841), the lowland Paca (Cuniculus paca Linnaeus, 1766), and the variegated squirrel (Echinosciuris variegatoides Ogilby, 1839). 2) leucism in the Central American agouti (Dasyprocta punctata J. E. Gray, 1842), and 3) erythrism in the northern Tamandua (Tamandua mexicana Saussure, 1860). We discuss some implications of these observations and the importance of gathering this type of data for developing more complex studies in the future.