One-Parameter GHG Emission Policy with R&D-based Growth

This document examines the GHG emission policy of regions which use land, labor and emitting inputs in production and enhance their productivity by devoting labor to R&D, but with different endowments and technology. The regions also have different impacts on global pollution. The problem is to organize common emission policy, if the regions cannot form a federation with a common budget and the policy parameters must be uniform for all regions. The results are the following. If a self-interested central planner allocate emission caps in fixed proportion to past emissions (i.e. grandfathering), then it establishes the Pareto optimum, decreasing emissions and promoting R&D and economic growth

International Emission Policy with Lobbying and Technological Change

I examine the implementation of emission policy in a union of countries. Production in any country incurs emissions that pollute all over the union, but efficiency in production can be improved by research and development (R&D). I compare four cases: laissez-faire, Pareto optimal policy, lobbying with centrally-determined emission quotas and lobbying with emission trade. The main findings are as follows. With emission quotas, the growth rate is socially optimal, but welfare sub-optimal. Emission trade speeds up growth from the initial position of laissez-faire, but slows down from the initial position of centrally-determined emission quotas

Population density and group size effects on reproductive behavior in a simultaneous hermaphrodite

<p>Abstract</p> <p>Background</p> <p>Despite growing evidence that population dynamic processes can have substantial effects on mating system evolution, little is known about their effect on mating rates in simultaneous hermaphrodites. According to theory, mating rate is expected to increase with mate availability because mating activity is primarily controlled by the male sexual function. A different scenario appears plausible in the hermaphroditic opisthobranch <it>Chelidonura sandrana</it>. Here, field mating rates are close to the female fitness optimum, suggesting that mating activity remains unresponsive to variation in mate availability.</p> <p>Results</p> <p>Applying an experimental design that aims at independent experimental manipulation of density and social group size, we find substantial increases in mate encounter rate with both factors, but no statistically detectable effects on mating rate in <it>C. sandrana</it>. Instead, mating rate remained close to the earlier determined female fitness optimum.</p> <p>Conclusions</p> <p>We demonstrate that mating rate in <it>C. sandrana </it>is largely unresponsive to variation in mate availability and is maintained close to the female fitness optimum. These findings challenge the prevailing notion of male driven mating rates in simultaneous hermaphrodites and call for complementary investigations of mating rate effects on fitness through the male sexual function.</p

Effects of Experimental Brood Size Manipulation and Gender on Carotenoid Levels of Eurasian Kestrels Falco tinnunculus

Animals use carotenoid-pigments for coloration, as antioxidants and as enhancers of the immune system. Carotenoid-dependent colours can thus signal individual quality and carotenoids have also been suggested to mediate life-history trade-offs.

Seasonal acclimatization to temperature in cardueline finches

1. Seasonal variation in body constituents and utilization of lipid, protein, and carbohydrate during cold stress in American goldfinches were studied to determine relations of these functions to the pronounced seasonal shift in thermogenic capacity documented in a previous study (Dawson and Carey, 1976).Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47119/1/360_2004_Article_BF00686746.pd

Kestrel hunting behaviour towards solitary and grouped Microtus agrestis and M. epiroticus — a laboratory experiment

Extensive field data show that avian and mammalian predators take more Microtus epiroticus than coexisting Microtus agrestis voles. The different vulnerability of these vole species may arise from prey selection or susceptibility differences between the two vole species. We studied the prey selection and hunting behaviour of the kestrel Falco tinnunculus on two Microtus voles, in addition to how behaviour and group structure in voles affect their vulnerability. The main results were that 1) kestrels do not select either of these species, but 2) susceptibility of the vole species deviates significantly. Falcons were more successful in catching M. epiroticus than M. agrestis, indicating that the latter is better in escaping avian predators and thus may have a lower cost of predation. During the experiment M. epiroticus aggregated more than M. agrestis but group size did not significantly explain capture success. However, solitary M. epiroticus seemed to be predated faster than those in groups. Although our results suggest that the high density of conspecifics may provide protection for vulnerable M. epiroticus, the aggregative distribution in the field and the preference for an open uncovered habitat may expose them to patch-searching predators.peerReviewe