London, United Kingdom, February 13, 2008—Vale, a four-week-old titi monkey, is held by his father Thiago, in the London Zoo's new rain forest biome.

The red titi monkey was born in January to his mother Yara, but the zoo chose Valentine's Day week to announce the birth after giving the baby a few weeks to acclimatize in the biome, according to a news release on the Zoo's Web site.

“This birth proves that Clore Rainforest Lookout really is a great enclosure for the animals, allowing them to behave and breed naturally. We are all delighted to see Vale zipping around the indoor forest on Yara's back," the Zoological Society of London's curator of mammals, Malcolm Fitzpatrick, said.

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