Anti afforestation ants
ANTS ARE hindering the return of forests on millions of hectares of abandoned pastures in Brazil by feeding on seeds of trees. According to a team of Brazilian and American researchers, two ant species -- Pheidole puttemansi and Solenopsis aurea found in the grasslands -- are voracious consumers of tree seeds (New Scientist, Vol 138, No 1874).
Another ant species -- Atta sexdens -- eats both seeds and tree seedlings. However, A sexdens ants are also forest-friendly. They cut leaves that fall to the ground and help increase soil fertility. But the dominant species is Wasmannia auropunctata, which aggressively defends its territory and attacks forest-friendly ants.