Comedora de hojas (202)
|I took this picture last month, in the fields of the “Simón Bolívar University”, near Caracas, Venezuela, where I received my degree several years ago. |
I remembered the existence of this large ant’s nest, and came back to found it were still there at the same place, and thousands of ants were working relentless, forming marching lines of hundred meters, to cut the leaves from surrounding trees and carry them to their nests in order to prepare their food.
I was fascinated with the organization and behavior of this insects. That’s why I’m posting as a workshop a composition of several pictures of this ants in action, as a complement.
Hope you like it.
Handheld with IS, about noon, brilliant sun and almost no clouds.
Crop, some contrast, sharpen and resized.
Leafcutter ants cut leaves from plants and trees and grow fungus on these cut fragments. The ants use this fungus to feed their larvae (the ants themselves mostly imbibe plant sap from the cut leaf fragments). The true leafcutters are restricted to two genera of ants (Atta and Acromyrmex) comprising a total of about 38 species.
Leaf cutter ants are limited to the arid, semi-tropical and tropical regions of South, Central, and North America, but they are one of the ecologically-dominant ants everywhere they are found.
Leaf cutter ants have one of the most sophisticated animal societies in the world. This is because of their unusual method of farming (they are the only animal besides humans who grow their own food from living matter), their extremely large colony sizes (up to 8 million individuals per colony in one species, Atta sexdens), and their fantastic caste system (with ants of different sizes and forms specialized for various tasks in the colony).
In order to protect their fungus cultures and combat invading fungi pests, these ants employ antibiotics produced by a Streptomyces bacteria that lives on their skin, in addition to physically removing the invading fungi. This interaction between ant, bacteria, and fingus crop is one of the most intricate examples of mutualism in nature.
The leafcutter nests, especially of the Atta spp, are marvels of engineering. Mature colonies sometimes fuse together to form one huge mound. In this case, the central nest mound may be 30 m in diameter, and may occupy 30 to 600 square meters!