My study area lies on the planet Tekuo. Tekuo is a parallel Earth that has been diverging from our world since the end of the Jurassic Age, some 150 million years ago.
Naturally, the planet’s dimensions are the same as ours, its year the same length, and its present is our present.
Over the millenia differences have accumulated between Tekuo and Earth, though some things predate the split and remain unaltered. Much about Tekuo, then, is new and much is familiar, too.
Geological plates have behaved in different ways, so all the continents are in different places. They have been subjected to different stresses and strains, and folded in different ways. This means that mountains, rivers and coastlines are not always where we would expect to find them. Nevertheless, the continents are broadly recognisible.
For example, the continent of Aheku corresponds to our Africa, but it is further west and north than Africa. The island of Mohai lies off a northwestern extension of Aheku. Neither Mohai nor the extension have a counterpart in our world.
The land east of our Great Rift Valley has already rifted away. It has joined with the equivalents of Saudi Arabia and India to form part of another continent that has no counterpart on Earth. Tekuan Australia is joined to Asia, but the two Americas do not meet and much of our Europe and Middle East are underwater.
Older lifeforms were established before the break with Earth, so we would broadly recognise Tekuan fish, trees and insects. The class of mammals was established just before the break and lines of development laid down, but Tekuan mammals are noticeably different from ours.
Most strikingly, there are three species of intelligent hominid: the utai, tall, solitary and peaceable, the koron, short and aggressive, and the ikhe, who are most like the humans of Earth.