Conservatism and adaptability during squirrel radiation : what is mandible shape telling us?

SYNTHESYS Project from the European Community Research Infrastructure (NL-TAF-4084)Both functional adaptation and phylogeny shape the morphology of taxa within clades. Herein we explore these two factors in an integrated way by analyzing shape and size variation in the mandible of extant squirrels using landmark-based geometric morphometrics in combination with a comparative phylogenetic analysis. Dietary specialization and locomotion were found to be reliable predictors of mandible shape, with the prediction by locomotion probably reflecting the underlying diet. In addition a weak but significant allometric effect could be demonstrated. Our results found a strong phylogenetic signal in the family as a whole as well as in the main clades, which is in agreement with the general notion of squirrels being a conservative group. This fact does not preclude functional explanations for mandible shape, but rather indicates that ancient adaptations kept a prominent role, with most genera having diverged little from their ancestral clade morphologies. Nevertheless, certain groups have evolved conspicuous adaptations that allow them to specialize on unique dietary resources. Such adaptations mostly occurred in the Callosciurinae and probably reflect their radiation into the numerous ecological niches of the tropical and subtropical forests of Southeastern Asia. Our dietary reconstruction for the oldest known fossil squirrels (Eocene, 36 million years ago) show a specialization on nuts and seeds, implying that the development from protrogomorphous to sciuromorphous skulls was not necessarily related to a change in diet

Diversidade de morcegos (Chiroptera, Mammalia) em fragmentos florestais no estado do Paraná, Brasil Diversity of bats (Chiroptera, Mammalia) in forest fragments

<abstract language="eng">The bay of the Tibagi river, a place which goes through quick environmental alterations, has three forest fragments: the "Floresta Nacional do Irati" (3.572 ha), the "Reserva Biológica da Klabin" (11.116 ha) and the "Parque Estadual Mata dos Godoy" (680 ha). Here, Myotis ruber (E. Geoffroy, 1806) and Chiroderma doriae Thomas, 1891 can be found, these are threatened bats, and three species, Pygoderma bilabiatum (Wagner, 1843), Myotis levis (I. Geoffroy, 1824) and Rogheessa tumida H. Allen, 1866, which are presumably threatened. Using the same effort of capture in the three places, it was stated that the "Floresta Nacional do Irati" with low vegetation diversity, showed nine species of bats. The "Parque Estadual Mata dos Godoy", although it's five times smaller, fifteen species. We came to the conclusion that a big reserve, without good conditions would house a lower number of species. A small reserve with adequate resources and great vegetation diversity presents a higher number of niches, housing a higher number of species

Morcegos (Chiroptera) da área urbana de Londrina, Paraná, Brasil Bats (Chiroptera) of the urban area of Londrina, Paraná, Brazil

<abstract language="eng">Study carried out within the urban perimeter of Londrina, which is located in the North of the state of Paraná. The objectives were the identification of urban species of bats and diurnal roosts used by them and the verification of the problems they can cause to the population. The fire brigade, the Autarquia Municipal do Ambiente de Londrina (Municipal Environment Autarchy of Londrina), the Biology Department of the Universidade Estadual de Londrina (State University of Londrina) and local residents helped spot the roosts. The collections were carried out in regular intervals between April 1998 and March 1999. By the end of them, 815 bats of 23 different species had been captured. Among these, 12 were found near or inside human constructions: Noctilio albiventris Desmarest, 1818; Artibeits lituratus (Olfers, 1818); Platyrrhinus lineatus (E. Geoffroy, 1810); Eptesicus brasiliensis Desmarest 1819; Lasiurus bore-alls (Muller 1776); Lasiurus ega (Gervais, 1856); Eumops glaucinus (Wagner, 1843); Molossus rufus (E. Geoffroy, 1805); Molossus molossus (Pallas, 1766); Nyctinomops laticaudatus (E. Geoffroy, 1805); Nyctinomops macrotis (Gray, 1840) e Tadarida brasiliensis (i. Geoffroy, 1824). Roost sites comprised expansion joints, roofs, attics and parks, among others. It can be concluded that bats are treated as undesirable animals by the population due to the lack of knowledge about the subject

A dieta dos morcegos frugívoros (Mammalia, Chiroptera, Phyllostomidae) de um pequeno remanescente de Floresta Estacionai Semidecidual do sul do Brasil The diet of fruit-eating bats (Mammalia, Chiroptera, Phyllostomidae) in a small Semideciduous Seasonal Forest remnant in south Brazil

<abstract language="eng">The diet of some leaf-nosed frugivorous bats - Artibeus Leach, 1821, Carollia perspicillata (Linnaeus, 1758) and Sturnira lilium (e. Geoffroy, 1810) - was studied for nine consecutive months through faecal analysis of individuais captured with mist-nets in a small forest remnant of Paraná state, Brazil. The analysis revealed that Artibeus spp. exhibited preference for fruits of Ficus spp. and Carollia perspicillata for those of Piper spp., which is in accordance with the results of previous studies. But contrary to what was expected, fruit of Solanum spp. were not found for the diet of Sturnira lilium in spite of their high availabilily (16 species) in the study area and their known relationship with this bat genus. The species of consumed fruit belonged to several plant life forms (trees, bushes, and lianas) and occurred in several habitais. This result emphasizes the importance of keeping habitat diversity, especially in small isolated reserves. Most consumed fruits were green, in agreement with the chiropterochoric syndrome, but ali seeds were small due to limitations of the sampling method. Fruit species abundance in the study area did not seem to have influenced their consumption, but intra-specific fruit availability did so, since most fruits were consumed within their intra-annual peak of availability

Land use history and population dynamics of free-standing figs in a maturing forest

<div><p>Figs (<i>Ficus</i> sp.) are often considered as keystone resources which strongly influence tropical forest ecosystems. We used long-term tree-census data to track the population dynamics of two abundant free-standing fig species, <i>Ficus insipida</i> and <i>F</i>. <i>yoponensis</i>, on Barro Colorado Island (BCI), a 15.6-km² island in Lake Gatún, Panama. Vegetation cover on BCI consists of a mosaic of old growth (>400 years) and maturing (about 90–150 year old) secondary rainforest. Locations and conditions of fig trees have been mapped and monitored on BCI for more than 35 years (1973–2011), with a focus on the Lutz Catchment area (25 ha). The original distribution of the fig trees shortly after the construction of the Panama Canal was derived from an aerial photograph from 1927 and was compared with previous land use and forest status. The distribution of both fig species (~850 trees) is restricted to secondary forest. Of the original 119 trees observed in Lutz Catchment in 1973, >70% of <i>F</i>. <i>insipida</i> and >90% of <i>F</i>. <i>yoponensis</i> had died by 2011. Observations in other areas on BCI support the trend of declining free-standing figs. We interpret the decline of these figs on BCI as a natural process within a maturing tropical lowland forest. Senescence of the fig trees appears to have been accelerated by severe droughts such as the strong El Niño event in the year 1982/83. Because figs form such an important food resource for frugivores, this shift in resource availability is likely to have cascading effects on frugivore populations.</p></div