YET another dividing line crumbles, the old certainties revealed to be, frankly, wrong: one of the few things that we thought survived from the critical mauling of Genesis was humankind's differentiation from the rest of the animal kingdom by virtue of its unique power to reason and think.

Alas! Inside the Animal Mind (BBC2, Tuesday of last week) demonstrated that some of our fellow species share the ability to consider a problem and work out a solution far more complex than can be categorised as reflex action. The brightest seem not to be our closest evolutionary relatives, the apes, but the corvid family, which includes crows and cockatoos.

We saw some mind-boggling experiments in which a seemingly clumsy raven, confronted for the first time by bolts, nuts, and levers that had to be manipulated to release a tasty morsel, executed the necessary process with such alacrity that we needed to slow the film down to see how he did it.

Many animals use tools to help them reach the food that they desire. It can be demonstrated that they share with us the ability to transfer a methodology successful in one situation to another, new one; and the imagination to recognise the potential in a new object.

What matters is not the size of a creature's brain, but the size of the brain in relation to body mass. Large animals, it seems, need big brains to manage their bodies - this does not make them brighter. It is important to be an omnivore rather than to rely on a limited diet, and a crucial factor is the creature's sociability: even without complex language, clever animals can, by demonstration, pass on to their kin how they use tools and solve problems. I confidently expect a programme soon about a new machine that is able to detect the presence of an immortal soul.

I thought that I did not need another documentary about the lead-up to the First World War, but Royal Cousins at War (BBC2, Wednesday and Thursday of last week) combined both themes. The fact that Britain, Germany, and Russia were all ruled by grandchildren of Queen Victoria is curious enough, but this splendid programme found enough unfamiliar archive material to demonstrate that the intertwined family relationship was a crucial factor in the descent into war.

The private film of relaxed royal family holidays in Denmark held a terrible poignancy in light of the carnage that was to come. Tellingly, the monarch who constitutionally held no political power - our own George V - was the only one who came out of the war with his position strengthened. Wilhelm's and Nicholas's deeply conservative assumption of autocratic right ensured the extinction of the monarchy in their countries.

George's one crucial action was his secret demand that Lloyd George must withdraw the invitation to the Tsar to live in exile in Britain. He secured his own dynasty's survival from the perceived threat of Bolshevik revolution at home by signing, in effect, his cousin's family's death warrant.

It was a sobering and shocking meditation on power and responsibility, and on the tension between personal and public responsibility.