Let's talk about this tree. If we knock on its trunk, it will sound hollow. why?
This Cecropia tree, is an example of the pioneer plants, which grow very quickly and have a very effective seed dispersion. These adaptations give them an advantage in the competition for sunlight in the forest, to take advantage of temporary gaps with better access for sunlight. The Cecropia can produce up to 900,000 seeds every time it produces fruit, which can be several times a year. The fruit has little nutritional value, but it is sweet, attracting many different animals, which then disperse the seeds throughout the forest. The seeds are very small and hold very little energy reserves, so they are completely dependent on the sun to grow. However, the wide dispersion makes it possible to be in the right place at the right time, and when a tree falls and a clearing opens up, they are right there to absorb the necessary sunlight.
The rapid growth of the Cecropia allows it to take advantage of these spaces in a more efficient manner than most plants. The Cecropia̢۪s trunk is hollow to facilitate this rapid growth, which can be as much as 5 meters (16.4 ft.) per year! The hollow trunk allows the Cecropia to invest its energy in growth as opposed to creating a strong trunk. However, the hollow trunk also has its disadvantages: it limits the tree's stability and it cannot grow very high, so on many occasions it develops stilt roots at the base of the tree. The hollow trunk also facilitate cooperation with Azteca ants, the Cecropia provide them a place to live inside the trunk, as well as food: nectar that is exuded through special structures called extrafloral nectaries located at the base of its leaves. The ants, in return, protect their valuable house against the herbivores and some climbing plants that try to grow on top of the Cecropia, competing with it for sunlight.
Some Cecropias do not have cooperation with ants and are therefore more vulnerable to herbivores. However, even cooperation with the ants does not guarantee 100% protection. Some agile and creative animals like spider monkeys can steal leaves of the Cecropia and quickly escape from the ants to another tree to eat in peace, out of their reach. The Cecropia and the other pioneer plants have excellent reproductive success, but for a short term; when other trees that grow slower but taller outgrow them, they die from lack of sunlight.
