Resource allocation varies with parental sex and brood size in the asynchronously hatching green-rumped parrotlet (Forpus passerinus)

When eggs hatch asynchronously, offspring arising from last-hatched eggs often exhibit a competitive disadvantage compared with their older, larger nestmates. Strong sibling competition might result in a pattern of resource allocation favoring larger nestlings, but active food allocation towards smaller offspring may compensate for the negative effects of asynchronous hatching. We examined patterns of resource allocation by green-rumped parrotlet parents to small and large broods under control and food-supplemented conditions. There was no difference between parents and among brood sizes in visit rate or number of feeds delivered, although females spent marginally more time in the nest than males. Both male and female parents preferentially fed offspring that had a higher begging effort than the remainder of the brood. Mean begging levels did not differ between small and large broods, but smaller offspring begged more than their older nestmates in large broods. Male parents fed small offspring less often in both brood sizes. Female parents fed offspring evenly in small broods, while in large broods they fed smaller offspring more frequently, with the exception of the very last hatched individual. These data suggest male parrotlets exhibit a feeding preference for larger offspring—possibly arising from the outcome of sibling competition—but that females practice active food allocation, particularly in larger brood sizes. These differential patterns of resource allocation between the sexes are consistent with other studies of parrots and may reflect some level of female compensation for the limitations imposed on smaller offspring by hatching asynchrony

Against the odds? Nestling sex ratio variation in green-rumped parrotlets

We investigated nestling sex ratio variation in the green-rumped parrotlet (Forpus passerinus), a small neotropical parrot breeding in central Venezuela. There are strong theoretical reasons to predict a female-biased sex ratio in this system according to the local resource hypothesis; juvenile males are philopatric and there are high levels of competition between male siblings for access to breeding females. Data were collected from two breeding sites over a 14-year period incorporating 564 broods with a total of 2728 nestlings. The mean percentage of male nestlings across years was 51%. Despite extreme hatching asynchrony in this system and increased survival of earlier hatched offspring, there was no bias in sex allocation associated with egg sequence. Patterns in sex allocation were not associated with clutch size, age, or size of the breeding female or breeding site. The potential for selective resorption of eggs was considered; however, no significant relationship was found between extended laying intervals and the sex of subsequent eggs. Together, these results suggest that female parrotlets are unable to regulate the sex ratio of their clutch at laying or that facultative manipulation of nestling sex ratio may not confer a fitness benefit to breeders in these populations. Copyright 2004.Forpus passerinus; green-rumped parrotlet; laying interval; local resource competition; sex ratio

Interspecific Egg-dumping by a Violet-green Swallow in an Active Western Bluebird Nest

Volume: 119Start Page: 126End Page: 12

Data from: Data management, archiving and sharing for biologists and the role of research institutions in the technology-oriented age

Data are one of the primary outputs of science. Although certain sub-disciplines of biology have pioneered efforts to ensure their long-term preservation and facilitate collaborations, data continue to disappear, owing mostly to technological, regulatory and ideological hurdles. In this review, we describe the important steps towards proper data management and archiving, and provide a critical discussion on the importance of long term data conservation. We then illustrate the rise in data archiving through the Joint Data Archiving Policy and the Dryad Digital Repository. In particular, we discuss data integration and how the limited availability of large scale datasets can hinder new discoveries. Finally, we propose solutions to increase the rate of data preservation. For example, by generating mechanisms insuring proper data management and archiving, by providing training in data management, and by transforming the traditional role of research institutions and libraries as data generators towards managers and archivers

With Great Power Comes Great Responsibility: the Importance of Rejection, Power, and Editors in the Practice of Scientific Publishing

Peer review is an important element of scientific communication but deserves quantitative examination. We used data from the handling service manuscript Central for ten mid-tier ecology and evolution journals to test whether number of external reviews completed improved citation rates for all accepted manuscripts. Contrary to a previous study examining this issue using resubmission data as a proxy for reviews, we show that citation rates of manuscripts do not correlate with the number of individuals that provided reviews. Importantly, externally-reviewed papers do not outperform editor-only reviewed published papers in terms of visibility within a 5-year citation window. These findings suggest that in many instances editors can be all that is needed to review papers (or at least conduct the critical first review to assess general suitability) if the purpose of peer review is to primarily filter and that journals can consider reducing the number of referees associated with reviewing ecology and evolution papers.</p

Does publication in top-tier journals affect reviewer behaviour?

We show that when ecologists act as reviewers their reported rejection rates recommended for manuscripts increases with their publication frequency in high impact factor journals. Rejection rate however does not relate to reviewer age. These results indicate that the likelihood of getting a paper accepted for publication may depend upon factors in addition to scientific merit. Multiple reviewer selection for a given manuscript therefore should consider not only appropriate expertise, but also reviewers that have variable publication experience with a range of different journals to ensure balanced treatment. Interestingly since age did not relate to rejection rates, more senior scientists are not necessarily more jaded in reviewing practices