The phrase "are thought to derive" is correct and usable in written English.
It can be used when discussing beliefs or theories about the origins or sources of something.
Example: "These ancient artifacts are thought to derive from a long-lost civilization that once thrived in this region."
Alternatives: "are believed to originate" or "are considered to come from".
In carnivores, the tRNA-derived SINEs (tRNA SINEs), also known as CAN-SINEs, are thought to derive from tRNALys [ 17].
Crystallized abilities, which are thought to derive from fluid abilities, include vocabulary, general information, and knowledge about specific fields.
Their colorful shimmery and feathered headdresses, stringed instruments and distinctive dance moves are thought to derive from the Swedish and Finnish settlers who preceded the British to the lower Delaware River, in the sixteen-forties.
These three orders of living amphibians are thought to derive from a single radiation of ancient amphibians, and although strikingly different in body form, they are probably the closest relatives to one another.
Among believers amulets are thought to derive power from their connection with natural forces, from religious associations, or from being made in a ritual manner at a favourable time.
The government's crusade against whistle-blowers sends the message that the state's strategic interests in acting under the cover of unaccountable secrecy not only outweigh the rights of its citizens, which legitimate governments are instituted to protect, but also the principles of democratic government, from which liberal states are thought to derive the authority to act at all.
It's thought to derive from "munt", Afrikaans racist slang for a black person, deriving from the Bantu umuntu (person).
At one time most African fauna was thought to derive from elsewhere.
The name is thought to derive from Rha, a name once given to the Volga River, around which it grew wild.
The Tower's Yeoman Warders date back to 1485, and their nickname, beefeaters, is thought to derive from the daily ration of meat they received.
