Clutch size and malaria resistance

Geographic variation in calcium and clutch size

For over a half century numerous hypotheses have surfaced aimed at explaining a key life history trait, the evolution of clutch size in birds. A principal goal has been to explain why clutch size generally increases with latitude both within species and among closely related species. Most hypotheses have stressed food limitation, predation, or seasonality. I present a novel hypothesis to explai...

Malaria drug - resistance in Iran

Introduction: Malaria is a public health problem for approximately 2.4 billion people, 40% of the world’s population, particularly in the tropical and subtropical countries. Countries in Asia, and Latin America, the islands of the South, West, and central pacific ocean are all affected. Drug resistance is the greatest challenge in combating against malaria. Drug resistance in malaria is now w...

The offspring-size/clutch-size trade-off in mammals.

The Smith-Fretwell model for optimal offspring size assumes the existence of an inverse proportional relationship (i.e., trade-off) between the number of offspring and the amount of resources invested in an individual offspring; virtually all of the many models derived from theirs make the same trade-off assumption. Over the last 30 years it has become apparent that the predicted proportionalit...

Testing small clutch size models with Daphnia.

Life-history theory predicts that for small clutches, variance in egg size (between individuals) should decrease in a predictable invariant manner as clutch size increases. To test this, we studied Daphnia magna at 350 different food treatments and recorded the number of eggs and the volume of each egg for their first clutch. As predicted, we found that the relationship between clutch size and ...

Notes and Comments Directional Selection and Clutch Size in Birds