However, hominins discovered more recently are somewhat older than the molecular clock would suggest. "Sahelanthropus tchadensis", commonly called ""Toumai"" is about 7 million years old and "Orrorin tugenensis" lived at least 6 million years ago. Since little is known of them, they remain controversial because the molecular clock in humans has determined that humans and chimpanzees had an evolutionary split at least a million years later.