Keyword: life history

Range extension and natural history observations for the smoky bat (Amorphochilus schnablii)

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The narrow Pacific coastal region west of the Andes Mountains in South America is a hotspot of endemism, including at least seven bat species. One of the least known species from this region is Amorphochilus schnablii, a small, thumbless bat in the family Furipteridae (Order Chiroptera). There are few capture records and museum specimens for this species, leaving an incomplete picture of its geographic range and life history traits. Here we present a revised distribution map and demographic data based on captures of A. schnablii from a colony in southwestern Ecuador. This colony is located 30 km farther north than any other known colony and contains twice as many individuals as previously reported colonies. A total of 55 bats were captured in February and September of 2010–2011. Standard measurements were taken from all individuals and adult females were assessed for reproductive condition. By combining these new demographic data with previous records, we examined annual reproductive trends, which suggests a pattern of seasonal monoestry. Parturition appears to be timed to occur just before the onset of the rainy season in December or January, a pattern observed in many other Neotropical insectivorous bats. More captures are needed to better understand the distribution, ecology, and life history of A. schnablii, but given their rareness, survey data are difficult to obtain.

Extensión de rango geográfico y observaciones sobre la historia natural para el murciélago ahumado, Amorphochilus schnablii. La estrecha región costera del Pacífico al oeste de las montañas de los Andes en América del Sur es un punto de acceso al endemismo, que incluye al menos siete especies de murciélagos. Una de las especies menos conocidas de esta región es Amorphochilus schnablii, un pequeño murciélago de la familia Furipteridae (Orden Chiroptera). Hay pocos registros de captura y especímenes de museo para esta especie, lo que deja una imagen incompleta de su rango geográfico y sus rasgos de historia de vida. Aquí presentamos un mapa de distribución revisado y datos demográficos basados en capturas de A. schnablii de una colonia en el suroeste de Ecuador. Esta colonia se ubica 30 km más al norte que cualquier otra colonia conocida y contiene el doble de individuos que las colonias documentadas anteriormente. Un total de 55 murciélagos fueron capturados en febrero y septiembre de 2010–2011. Se tomaron medidas estándar de todos los individuos y se evaluó la condición reproductiva de las hembras adultas. Al combinar estos nuevos datos demográficos con registros previos, examinamos las tendencias reproductivas anuales, lo que sugiere un patrón de monoestasis estacional. El parto parece estar programado para ocurrir justo antes del inicio de la temporada de lluvias en diciembre o enero, un patrón observado en muchos otros murciélagos insectívoros neotropicales. Se necesitan más capturas para comprender mejor la distribución, la ecología y la historia de vida de A. schnablii, pero dada su rareza, los datos de censo son difíciles de obtener.

Social parasitism in mammals with particular reference to Neotropical primates

Organisms often respond in ways that appear to benefit others rather than themselves. This phenomenon is consistent with the views of Darwin (1859) and Dawkins (1999) that individuals may exploit the responses of others. This phenomenon, “social parasitism”, has been extensively investigated in social insects, particularly, ants. Other empirical studies have demonstrated social parasitism in fish, birds, and mammals. This paper reviews several possible examples of mammalian social parasitism, with an emphasis upon intraspecific social parasitism (ISP) in Neotropical primates. Social parasitism is discussed as a life history feature of long-lived, social organisms such as many primates, including humans. A simple mathematical model, applied to social parasitism, is presented linking parasite transmission to a parasite’s influence on its host. Phenotypic manipulation is assessed as a mechanism of social parasitism, and possible examples from the literature on Neotropical primates are provided. Social parasitism is discussed in relation to the evolution of higher grades of sociality (eusociality, cooperative breeding), manipulation success (infectivity), and the evolution of virulence (e.g., aggression, punishment). It is proposed that an understanding of variations in virulence and infectivity by social parasites is likely to reveal important evolutionary dynamics for an integrated view of social evolution.