Welcome Swallow

This Welcome Swallow, Hirundo neoxena, is just on the cusp of adulthood. This is no mean feat, as not only does it have to contend with predators like snakes, cats and hawks, but it also grows up in a filthy, disease-ridden nest. Scientists have calculated that hatchlings have up to four times as many immune-boosting white blood cells as adults, giving them an enormous booster shot to increase their survival rate Ð an evolutionary trick that has worked well for this young adult!