"The earliest written statements suggesting that the brown anole might negatively affect the native green anole, Anolis carolinensis, were made by Collette (1961), followed by King and Krakauer (1966), and reinforced by Lee (1985), but all these statements were based on anecdotes. Tokarz and Beck (1987) made the first attempts to study the interaction directly, followed by Brown and Echternacht (1991), approaching the problem from the standpoint of interference competition (aggression), but found that intraspecific (within species) overshadowed interspecific (between species) interactions. Campbell (2000) witnessed only three interspecific interactions during thousands of hours of field surveys in sympatric populations, but witnessed hundreds of intraspecific territorial squabbles. In other words, these territorial species fight much more amongst themselves than with other species."