Category archives: Evolution

Bees are coffee addicts too

Bees are coffee addicts too

BiologyEvolutionNeurobiology

By Francisco J Hernández

As the Hungarian mathematician Alfréd Rényi famously put it (although usually misattributed to Paul Erdös), mathematicians are devices for turning coffee into theorems. Other people drink coffee for a variety of reasons, and considering that coffee is very far from being the only popular beverage containing caffeine, it is not difficult to believe that caffeine […]

Triassic lungs: Unidirectional flow in alligators’ breathing

Triassic lungs: Unidirectional flow in alligators’ breathing

BiologyEvolutionPhysics

By Mireia Altimira

The lungs of birds move air in only one direction during both inspiration and expiration through a set of tubular gas-exchanging bronchi called parabronchi. On the other hand, in the lungs of mammals and other vertebrates, air moves tidally into and out of terminal gas-exchange structures, called alveoli (Figure 1). The work carried out by […]

Bears and riddles

Bears and riddles

BiologyEvolution

By Rafael Medina

You’re sitting in a room with an all-southern view. Suddenly, a bear walks by the window. What color is the bear? Young Sherlock Holmes. Barry Levinson (1985) The polar bear (Ursus maritimus) is one of the most unmistakable mammals of the planet. Its white fur is maybe the most straightforward reason for this distinctiveness, but […]

Ever since Wallace

Ever since Wallace

BiologyEvolution

By Rafael Medina

Alfred Russel Wallace (1823-1813) is especially known as one of the discoverers of evolution by natural selection. However, among his various contributions to the development of modern biology we can also consider the British naturalist as the father of biogeography: the study of the spatial distribution of organisms over the surface of the planet. Wallace’s […]

Hybridization: no longer the bad guy

Hybridization: no longer the bad guy

BiologyEvolutionGenetics

By Rafael Medina

It is interesting how some ideas get stuck in our minds even long after it is proved that they are incorrect or incomplete. Haeckel’s Recapitulation Theory, which states that during the embryological development of an organism it undergoes through different stages recalling the evolutionary history of its ancestors (ontogeny recapitulates phylogeny), is considered obsolete nowadays […]

When should a man be more interested in caring for his sister’s children than his wife’s?

When should a man be more interested in caring for his sister’s children than his wife’s?

AnthropologyEvolutionGenetics

By César Tomé

From the genetic point of view, when should a man be more interested in caring for his sister’s children than his wife’s? A quantitative analysis of Alan Rogers, University of Utah, shows that this behaviour should be the choice in populations where adultery is common or permitted. In the animal world, males caring for offspring […]