A pair of eastern pygmy marmosets, one of the most miniature primate species on Earth, arrived to parents Zoe (3) and Baldrick (4). The tiny twins each measure just two inches (five centimetres) in length and weigh no more than 10 grams. Keepers say the babies are already ??shighly inquisitive??? but are so small that it will be some time yet until their genders are known. Holly Webb, a Primate Keeper at Chester Zoo, said: ??sIt???s wonderful to see new additions within the marmoset family and it???s almost unbelievable just how small the babies are when they are first born. They are no bigger than a ping pong ball! ??sMum Zoe and dad Baldrick have jumped straight into parenthood. Zoe is ever so caring and, unlike other primates, dad is heavily involved in the upbringing of the youngsters. Baldrick sensed that Zoe was ready to give birth and even put on a little extra weight to give him the energy to care for the twins. He???s really got stuck into the parenting - we spotted him carrying the babies around on his back when they were just one day old. ??sNew babies always strengthen family bonds and some of the younger primates in the group have also been carrying the new arrivals around. It???s great to see them learn and pick up parenting tips from Zoe and Baldrick, and that experience will be important if they one day go on to have young of their own. The fact that younger members of the family are trusted to carry around such delicate new-borns, builds a lot of trust within the group. ??sThe babies are already very inquisitive and aware of their surroundings. I can???t wait to see them develop their own little personalities.??? The eastern pygmy marmoset is native to the rainforests of western Brazil, south-eastern Colombia, eastern Ecuador and eastern Peru. These miniature monkeys are threatened by habitat loss and often exposed to hunting or their capture for the illegal pet trade. Dr Nick Davis, Deputy Curator of Mammals at the zoo, said: ??sMany pr