Reproductive Evolution: Pulling the Plug on Selection

Mosquito biology. Evolution of sexual traits influencing vectorial capacity in anopheline mosquitoes.

The availability of genome sequences from 16 anopheline species provides unprecedented opportunities to study the evolution of reproductive traits relevant for malaria transmission. In Anopheles gambiae, a likely candidate for sexual selection is male 20-hydroxyecdysone (20E). Sexual transfer of this steroid hormone as part of a mating plug dramatically changes female physiological processes in...

Sperm competition and the evolution of male reproductive anatomy in rodents.

Sperm competition is a pervasive selective force in evolution, shaping reproductive anatomy, physiology and behaviour. Here, we present comparative evidence that varying sperm competition levels account for variation in the male reproductive anatomy of rodents, the largest and most diverse mammalian order. We focus on the sperm-producing testes and the accessory reproductive glands, which produ...

Reproductive Evolution: Symptom of a Selfing Syndrome

In the nematode Caenorhabditis elegans, a single gene (plg-1) encodes the dominant protein found in mating plugs - a means of inhibiting multiple matings. Naturally occurring loss of plg-1 function results in males that fail to deposit mating plugs - a manifestation of relaxed sexual selection since the evolution of self-fertilization in this species.

An Experimental Investigation of Spark Plug Temperature in Bi-fuel Engine and Its Effect on Electrode Erosion

Temperature is one of the effective parameters in erosion of spark plug electrodes. In this research, temperature of spark plug was measured in engine's different operation conditions with two types of fuels: compressed natural gas and gasoline. Test results showed that, temperature of center electrode is lower than ground electrode and maximum difference between them is 110ºC that occurs at...

Pulling the plug – halting cancer's theft of mitochondria