Scientists can sound so authoritative in their pronouncements. Examples abound. The "just so" stories concerning evolution (which I don't want to get into here), the big bang theory, or how about the one about tonsils being a vestigial organ serving no purpose. Doctors made a lot of money on that one when I was a kid!
Migration theories are another area where I think the jury is still out. Scientists have offered theories about how birds learn migration routes from their parents, or use the sun as a kind of global positioning device, or use an internal compass. When you begin with the wrong premise (either everything has evolved or everything has been created), whichever one is the lie is not going to lead you to a correct conclusion.
One of the problems is that migration is not necessarily like it is portrayed in Rio2. In the case of hummingbirds (and osprey, for that matter), mom, dad and the kids don't all leave together. All three migrate at different times! Males leave first, females later, and offspring last of all. So much for the idea of parents teaching their children well.
In speaking of hummingbird migration, one of the better birding books admits, "The precise guidance system involved in hummingbird migration is not known" (The Sibley Guide to Bird Life & Behavior, pg. 364). Yet, amazingly, these diminutive creatures navigate all the way to Mexico (most crossing the Gulf) and return to the same neighborhood the following spring. Birders banding birds during times of migration in Louisiana, have caught hummingbirds in mist nets on the same day as they were caught the previous year! Try getting that kind of precision out of a human.
Some birds are nocturnal migrants that are thought to navigate
by the stars, but that does not include hummingbirds.
One year we failed to put the hummingbird feeders out on time. The previous year we had one hanging from heavy-duty fishing line on the side of the garage. I was totally floored when a hummingbird appeared and flew up to examine the end of the empty fishing line. The only way she could have known that it once held a feeder was to have been in our yard the year before. That little incident raised my level of respect for their navigational abilities enormously.
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