The effect of testosterone injections on aggression and begging behaviour of black headed gull chicks

I wrote this article as part of my Bachelor of Science study at the University or Groningen in 2009. You can download the whole PDF below for free….

Estivation in desert mammals to cope with aridity

Low food availability and high energy expenditure are not exclusively found in cold winter climates, but can also occur in hot, dry climates in summer. Desert ecosystems face…

The costs and benefits of hibernation

Some animals hibernate to save energy in times of low energy intake, e.g. due to low food availability. What are the costs and benefits of hibernation? I’ll explain…

What is torpor in mammals?

The maintenance of a high body temperature is a considerable cost for small endothermic animals. Small animals have a relatively large surface to volume ratio resulting in high…

Balancing selection

Balancing selection means that two alleles are maintained in the population because of natural selection. You would expect that one allele will provide higher fitness than the other,…

The evolution of eusociality

If there is a gene that makes you eusocial, making you raise the offspring of other individuals, how does it spread? How can your eusocial gene end up…

Genetic diversity

Genetic diversity is the term for the diversity of the genetic material in a population or species. More different genes inside the population means a higher genetic diversity….

The paradox of sexual reproduction

The existence of sexual reproduction has baffled biologist for centuries. How can sexual reproduction have evolved when it greatly diminishes the speed of reproduction? How can it continue…

Asexual reproduction

Asexual reproduction is the term for reproduction that only involves one parent individual. The parent produces an offspring without genetic contribution of another individual of its species. As…

Sexual reproduction

Sexual reproduction is the term for reproduction that involves recombining genes of two different individuals to form a new individual. The new individual will have genes / alleles…