WHISTLING THORN VACHELLIA DREPANOLOBIUM
Look closely at this acacia and you will notice that it produces long, straight spines, always in pairs and often with a large bulbous base. Look closer still and you will find tiny entry/exit holes in these swollen nodes which have been made by ants. Tree and insect have formed a mutualistic relationship: the ant enjoys a thorny shelter and nectar on tap, while the tree appears to benefit from its in-house legion of herbivore deterrents. Sit quietly and observe this evolutionary wonder at work and you may well hear the tree whistling softly as the breeze blows across the countless holes of its ant abodes.