An international report reveals almost half the world's monkeys and apes are facing a worsening threat of extinction because of deforestation and hunting.

Around 634 species were included in the report, of those 48 percent were classified as being threatened by extinction.

In the past studies have shown that the larger species of primates such as gorillas, chimpanzees and orang-utans were highly threatened but now a lot more is known about the threat to some of the smaller species such as tamarins, marmosets and a section of the lemurs.

Hayley Platt reports.