I would suggest adding Theodosius Dobzhansky's
Genetics and the Origin of Species (1937, Columbia Uni Press) to your list. Another is Ernst Mayr's
Animal Species and Evolution, (1963, Belknap/Harvard Uni Press).
I guess everybody has their favorites. For ecology, obviously the Wilson/MacArthur book you mentioned is one of the most influential, putting the science on a sound theoretical footing for the first time. For modern conservation theory, Wilson's
Biodiversity, (1988, National Academy Press), is among the most influential.
What is interesting is that - while considering your OP - I started to think about which books were the most
personally influential in launching me in my chosen career. I know that this isn't directly related to the OP, but the most influential I came up with was an early childhood gift of Rachel Carson's
Silent Spring, (1962, Houghton-Mifflin), which I read around age 10 or so. Amazing what early exposure to science can do for someone.