In one case, an orangutan cringed and pulled away as its companion extracted a fish from a pond.
The orangutan finding, he says, suggests these fossils may indeed represent bipedal apes.
Present day orangutan and spider monkeys have the same angle as humans yet are extremely adept tree climbers.
Later investigation revealed that the door that connects the furnace room to the orangutan enclosure was open.
Climbing slowly and deliberately the way an orangutan does puts a lot of stress on limb bones, she says.
Too much vibration and an orangutan can be thrown off altogether.
The orangutan evidence adds a new twist to the debate of arboreal versus terrestrial bipedalism theories.
In addition, there was variability in preference rankings across time for each orangutan.
Word Origin and History for orangutan
1699, from Du. orang-outang, from Malay orang utan, lit. "man of the woods," from orang "man" + utan, hutan "forest, wild." It is possible that the word originally was used by town-dwellers on Java to describe savage forest tribes of the Sunda Islands and that Europeans misunderstood it to mean the ape. The name is not now applied in Malay to the animal, but there is evidence that it was so in 17c.