A chimpanzee looks at tourists from inside of the wire netting in Tacugama Chimpanzee Sanctuary of Sierra Leone, April 28, 2014. Located close to Freetown, the capital of Sierra Leone, Tacugama Chimpanzee Sanctuary covers 0.4 sqaure kilometers of the 176.88 sqaure kilometers Western Area Peninsula Forest Reserve. Established by Bala Amarasekaran in 1995, Tacugama now cares for over 100 chimpanzees under the work of nearly 30 staffs in several forested enclosures. (Xinhua/Lin Xiaowei)

The bulletin board shows various kinds of chimpanzee's "language" in the form of comics in Tacugama Chimpanzee Sanctuary of Sierra Leone, April 28, 2014. Located close to Freetown, the capital of Sierra Leone, Tacugama Chimpanzee Sanctuary covers 0.4 sqaure kilometers of the 176.88 sqaure kilometers Western Area Peninsula Forest Reserve. Established by Bala Amarasekaran in 1995, Tacugama now cares for over 100 chimpanzees under the work of nearly 30 staffs in several forested enclosures. (Xinhua/Lin Xiaowei)

A chameleon crawls in the forest of Tacugama Chimpanzee Sanctuary in Sierra Leone, April 28, 2014. Located close to Freetown, the capital of Sierra Leone, Tacugama Chimpanzee Sanctuary covers 0.4 sqaure kilometers of the 176.88 sqaure kilometers Western Area Peninsula Forest Reserve. Established by Bala Amarasekaran in 1995, Tacugama now cares for over 100 chimpanzees under the work of nearly 30 staffs in several forested enclosures. (Xinhua/Lin Xiaowei)

A baby chimpanzee enjoys oranges in Tacugama Chimpanzee Sanctuary of Sierra Leone, April 28, 2014. Located close to Freetown, the capital of Sierra Leone, Tacugama Chimpanzee Sanctuary covers 0.4 sqaure kilometers of the 176.88 sqaure kilometers Western Area Peninsula Forest Reserve. Established by Bala Amarasekaran in 1995, Tacugama now cares for over 100 chimpanzees under the work of nearly 30 staffs in several forested enclosures. (Xinhua/Lin Xiaowei)

Chimpanzees wait for food in Tacugama Chimpanzee Sanctuary of Sierra Leone, April 28, 2014. Located close to Freetown, the capital of Sierra Leone, Tacugama Chimpanzee Sanctuary covers 0.4 sqaure kilometers of the 176.88 sqaure kilometers Western Area Peninsula Forest Reserve. Established by Bala Amarasekaran in 1995, Tacugama now cares for over 100 chimpanzees under the work of nearly 30 staffs in several forested enclosures. (Xinhua/Lin Xiaowei)