The United Kingdom's constitution, being uncodified and largely unwritten, makes no mention of a prime minister. Though it had de facto existed for centuries, its first mention in official state documents did not occur until the first decade of the twentieth century. Accordingly, it is often said "not to exist", indeed there are several instances of parliament declaring this to be the case. The prime minister sits in the cabinet solely by virtue of occupying another office, either First Lord of the Treasury (office in commission), or more rarely Chancellor of the Exchequer (the last of whom was Balfour in 1905).
When was prime minister first mentioned in a government document in the UK?
first decade of the twentieth century

The Caribbean initially provided England's most important and lucrative colonies, but not before several attempts at colonisation failed. An attempt to establish a colony in Guiana in 1604 lasted only two years, and failed in its main objective to find gold deposits. Colonies in St Lucia (1605) and Grenada (1609) also rapidly folded, but settlements were successfully established in St. Kitts (1624), Barbados (1627) and Nevis (1628). The colonies soon adopted the system of sugar plantations successfully used by the Portuguese in Brazil, which depended on slave labour, and—at first—Dutch ships, to sell the slaves and buy the sugar. To ensure that the increasingly healthy profits of this trade remained in English hands, Parliament decreed in 1651 that only English ships would be able to ply their trade in English colonies. This led to hostilities with the United Dutch Provinces—a series of Anglo-Dutch Wars—which would eventually strengthen England's position in the Americas at the expense of the Dutch. In 1655, England annexed the island of Jamaica from the Spanish, and in 1666 succeeded in colonising the Bahamas.
When did England colonize the Bahamas?
1666

The Arabian oryx, a species of large antelope, once inhabited much of the desert areas of the Middle East. However, the species' striking appearance made it (along with the closely related scimitar-horned oryx and addax) a popular quarry for sport hunters, especially foreign executives of oil companies working in the region.[citation needed] The use of automobiles and high-powered rifles destroyed their only advantage: speed, and they became extinct in the wild exclusively due to sport hunting in 1972. The scimitar-horned oryx followed suit, while the addax became critically endangered. However, the Arabian oryx has now made a comeback and been upgraded from “extinct in the wild” to “vulnerable” due to conservation efforts like captive breeding
What contributed to the Arabian oryx rise from extinct to vulnerable?
conservation efforts