Not only has Alf said that Mudokons are human-sized, but there have been references to Glukkons being 7-foot tall and also, I think, a picture of various Oddworld critters standing in front of one of these height-measuring walls you see in American police stations on TV, which showed Mudokons to be 6-foot tall.
And don't try and tell me that imperial measurements on Oddworld are ten-times the length as their Earthly equivalents.
