In the late 1950's, scientists in South America imported African honeybees to breed with honeybees native to the region. The scientists hoped the hybrid bees would produce more honey. Some of the African bees escaped their hives and began breeding in the wild in large numbers. The African bees have outcompeted native bees for resources, decreasing the number of native honeybees. The African bees that have escaped into the environment are:
a. a climax community
b. an invasive species
c. a pioneer species
d. an ecological succesion