Species coexistence by wide constant size spacing.

We consider the distribution of fruit pigeons of the genera and on the island of New Guinea. Of the 21 species, between six and eight coexist inside humid lowland forests. We conducted or analyzed 31 surveys at 16 different sites, resurveying some sites in different years.

Reversals of national fortune, and social science methodologies.

Among non-European regions colonized by Europeans, regions that were relatively richer five centuries ago (like Mexico, Peru, and India) tend to be poorer today, while regions that originally were relatively poorer (like the United States, Chile, and Australia) tend now to be richer. Acemoglu, Johnson, and Robinson (abbreviated AJR) established the generality of this reversal of fortune. Chanda, Cook, and Putterman (abbreviated CCP) have now reanalyzed it, taking as a unit of analysis populations rather than geographic regions.

Explosive Pleistocene diversification and hemispheric expansion of a "great speciator".

Factors that influence speciation rates among groups of organisms are integral to deciphering macroevolutionary processes; however, they remain poorly understood. Here, we use molecular phylogenetic data and divergence time estimates to reconstruct the pattern and tempo of speciation within a widespread and homogeneous bird family (white-eyes, Zosteropidae) that contains an archetypal "great speciator." Our analyses show that the majority of this species-rich family constitutes a clade that arose within the last 2 million years, yielding a per-lineage diversification rate among the highest reported for vertebrates (1.

Origins of major human infectious diseases.

Many of the major human infectious diseases, including some now confined to humans and absent from animals, are 'new' ones that arose only after the origins of agriculture. Where did they come from? Why are they overwhelmingly of Old World origins? Here we show that answers to these questions are different for tropical and temperate diseases; for instance, in the relative importance of domestic animals and wild primates as sources. We identify five intermediate stages through which a pathogen exclusively infecting animals may become transformed into a pathogen exclusively infecting humans.

Breeding birds on small islands: island biogeography or optimal foraging?

1. We test MacArthur and Wilson's theory about the biogeography of communities on isolated habitat patches using bird breeding records from 16 small islands off the coasts of Britain and Ireland. 2.

Regulation of gut function varies with life-history traits in chuckwallas (Sauromalus obesus: Iguanidae).

We examined the effects of hibernation and fasting on intestinal glucose and proline uptake rates of chuckwallas (Sauromalus obesus) and on the size of organs directly or indirectly related to digestion. These lizards show geographic variation in body size and growth rate that parallels an elevational gradient in our study area. At low elevation, food is available only for a short time during the spring; at high elevation, food may also be available during summer and autumn, depending on rainfall conditions in a given year.