Quirks and Quarks19:53Our planet’s circulatory system depends on animals eating, excreting and expiring From the tiniest insects to the largest whales, biologist Joe Roman says animals play an ...

Water and nutrients are important to keep living things alive and healthy. Animals, including humans, get these from what they eat and drink, but how do the water and nutrients get transported around ...

Stay close, please, children. We are here at the riverbank to look at the way different animal circulation systems move blood around their bodies. This furry creature is a water vole. Like all mammals ...

A circulatory system that beats gravity. Spots that dissipate heat. This giant is purpose-built for its size and surroundings. This story appears in the October 2019 issue of National Geographic ...