'Swifts use this thick and gummy substance to hold their nests together'
saliva
ODD ANIMAL FACTS: Swifts use this thick and gummy substance to hold their nests together
Swifts use this thick and gummy substance to hold their nests together
Swifts use this thick and gummy substance to hold their nests together
ODD ANIMAL FACTS
saliva
ODD ANIMAL FACTS