Emperor Akihito of Japan is a published marine biologist

I'll quote at length from the excellent https://www.amazon.com/dp/1780747411/ :

> As mentioned before, the king was widely regarded as a link between the divine and the human worlds. He might be a god himself, or descended from one, or simply appointed by the deity, but at all events he was expected to use his 'divine effulgence' (as the Persians called it) or his Heil (as the Germanic barbarians called it) for the benefit of the community: this was the crucial manner in which he promoted welfare. He was expected to maintain and embody the law in the sense of cosmic, natural and human order, partly by acting as the symbolic head of the community and partly by observing the right ways and setting a good example. If he did so, happiness and prosperity would ensue.

> Such ideas are widely attested for primitive societies, but they displayed an amazing tenacity under civilized conditions, being attested for ancient Egypt, China, Japan, South-East Asia (where some kings had no other functions), India, Iran, the Islamic world (in both the concept of the caliphate and that of kingship), as well as the Hellenistic world and Europe. If the king was just, rain would fall; if he was not, famine, flood and other natural disasters would ensue. Natural disasters were thus blamed on the king: they proved that he had misbehaved. Under a good king, 'vices decrease and virtues increase... the world becomes prosperous and joyous', as the Zoroastrians explained; but 'when kings are unjust, even sugar and salt lose their flavour', as the Indians put it. If no king existed, both the natural and the human order would dissolve and chaos would prevail: a country without a king enjoyed 'neither rain nor seed, neither wealth nor wife, neither sacrifices nor festivals', according to the Ramayana; people suffered illness, customs ceased to exist and all was nothingness according to Malay literature. It is for this reason that the sixteenth-century Burmese king laughed at the idea of a kingless Venice; and it is for the same reason that the British abolition of the Burmese monarchy in 1886 was a catastrophic shock to the Burmese which the British had not anticipated.

> Ritual kingship (as this role is commonly called) might require no action at all: the Japanese emperors performed it for over a thousand years by simply existing, being kept in such ceremonious inactivity that when one of them made a bid for real power he could scarcely even walk. Most rulers, however, combined their ritual role with co-ordinating and warlike functions which tended to transform or eclipse it, while at the same time the development of specialized religious institutions changed their standing vis-à-vis the divine.

(Posted as three quotes to mirror the two paragraph breaks within the section I wanted to quote. I have not omitted or altered any text within the quoted section.)

Note also that this is the current function of the Queen of England.