How do biparental species optimally provision young when begging is honest?

Begging for control : when are offspring solicitation behaviours honest ?

Geoff A. Parker Population and Evolutionary Biology Research Group, Nicholson Building, School of Biological Sciences, University of Liverpool, Liverpool, UK L69 3GS. Ever since Trivers [1] showed that parents and their offspring could be in conflict over the amount of parental investment, the evolution and maintenance of begging behaviour has been an area of increasing interest to evolutionary...

Chick begging as a signal: are nestlings honest?

Begging by dependent avian offspring is known to correlate with hunger level, and parents use this as a signal of brood demand to adjust their chick feeding behavior. While there is information on how each chick adjusts its begging to its own condition, little is known of how chicks adjust to the state of their nest mates. In two experiments we manipulated the competitive environment of individ...

How Do We Know When an Organic Compound Is Pure?

he separation of mixtures of compounds to give the pure components is of T great practical importance in chemistry. ~ 2 n ~ synthetic reactions give mixtures of products and it is necessary for you to have a reasonably clear idea of how mixtures of compounds can be separated. Almost all compounds of biochemical interest occur naturally as components of very complex mixtures from which they can ...

When is sleepiness a disease? How do we measure it?

How Do Young People Choose

Previous studies on the determinants of the choice of college major have assumed a constant probability of success across majors or a constant earnings stream across majors. Our model disregards these two restrictive assumptions in computing an expected earnings variable to explain the probability that a student will choose a specific major among four choices of concentrations. The construction...