The long-lived Grandidier’s baobab is in leaf from October to May, and flowers between May and August (2). The flowers, said to smell of sour watermelon, open just before or soon after dusk, and all the pollen is released during the first night (2). It is pollinated by nocturnal mammals, such as fork-marked lemurs. They move through the canopies, inserting their snouts into the white flowers and licking nectar from the petal bases, resulting in pollen being deposited in the lemur’s face (3).
Grandidier’s baobab bears ripe fruit in November and December (2). Unlike the baobabs of Africa and Australia, it appears that the seeds of the tasty fruit are not dispersed by animals. Lemurs are the only living animals on Madagascar that are capable of acting as seed dispersers, yet this has never been documented (2). In the past however, this could have been very different. There are several species that became extinct since human colonisation of the island, 1,500 to 2,000 years ago, that could very likely have been dispersers of the seeds. This includes species of primates that were thought to be similar to baboons, and the heaviest bird that ever lived, the elephant bird, which had a powerful beak that could have opened large fruit (2). Today, water may be the means by which the seeds are dispersed (2).
On the tropical island of Madagascar, a lack of water can sometimes be a problem for its inhabitants. It appears that the baobab overcomes this by storing water within the fibrous wood of the trunk, as the tree’s diameter fluctuates with rainfall (2).