In Neotropical wet forests several species of omnivorous, resource-defending ants, live and forage in close proximity to one another. Although the forest floor is heterogeneous in microhabitat and food quantity, little is known about the impact of microhabitat and food variation upon resource monopoly among ants. We investigated how food type and microhabitat influence food monopoly in resource...

Abstract Interspecific territoriality has complex ecological and evolutionary consequences. Species that interact aggressively often exhibit spatial or temporal shifts in activity reduce the frequency of costly encounters. We analyzed data collected over a 13-year period on 50 populations rubyspot damselflies (Hetaerina spp.) to examine how rates interspecific fighting covary with fine-scale ha...

Conventional models of single district plurality elections show that with three parties anything can happen extreme policies can win regardless of voter preferences. I show that when there are multiple district elections for a legislature we get back to a world where the median voter matters: an extreme policy will generally only come about if it is preferred by the median voter in a majority o...

We consider a multilateral bargaining game in which the agents can be classified into two groups according to their instantaneous preferences. In one of these groups there is one agent with a different discount factor. We analyze how this time-preference heterogeneity may generate multiplicity of equilibria. When such an agent is sufficiently more patient than the rest, there is an equilibrium ...

1. Microhabitat use and antipredator behaviour (i.e. behavioural response to a bird model and refuge microhabitat) was measured in an experimental set-up for 11 lacertid lizard species. Additionally, locomotor performance (sprint speed, climbing and clambering speed, manoeuvrability and endurance) of the same species was quantified. 2. The results showed considerable interspecific variation in ...

Live scleractinian corals are a prime microhabitat for many recruiting coral reef fishes, yet live coral cover has exhibited widespread declines, and the impact of this loss on recruiting fishes is not well understood. Although reduced recruitment rates of parrotfishes (Scaridae) have been observed after loss of coral cover, increased juvenile parrotfish abundance observed in connection with in...

Gobies (Teleostei: Gobiidae) are an extremely diverse and widely distributed group and are the second most species rich family of vertebrates. Ecological drivers are key to the evolutionary success of the Gobiidae. However, ecological and phylogenetic data are lacking for many diverse genera of gobies. Our study investigated the evolution of microhabitat association across the phylogeny of 18 s...

We studied the ecology of Tropidurus itambere and T. oreadicus that occur syntopically in rocky habitats of Cerrado vegetation in central Brazil during the dry season (April to September 2000). The two species are ecologically similar, but somewhat differentiated in vertical microhabitat use. The two species preferred rocky surface microhabitat. Both species demonstrated a unimodal activity pat...