Like to watch flower visitors? I do, although other folks may have more exciting hobbies. A great flower for pollinator-watching is Carolina Redroot (Lachnanthes caroliana). Everybody comes along: butterflies, wasps, beetles, bees, and who knows what else. Here’s a sampler from just today:
When it comes to beautiful bugs, why pick favorites? But the visitors who piqued my biological curiosity today were bumblebees in connection with their warning coloration. A few words on that: Creatures and plants benefit from not being eaten, duh. That’s why, double duh, there are so many defensive mechanisms ranging from stinky skunks to rhinoceros horns. Now let’s say you’re a well-armed bug, perhaps deadly poisonous or with a wicked sting. That helps of course, and it helps even more to not be attacked to begin with: thus warning coloration. Try to eat me, and YOU’LL REGRET IT! Now let’s say you are harmless and likewise benefit from not being attacked. If you look like something able to hurt an attacker, warning colors protect the harmless too. We’ve all seen it: things that sting and the mere posers use yellow and orange bands and blotches mixed with black to say “let me bee.” Okay, with that obvious foundation, here’s the cool part (as I see it).
Bumblebees have warning coloration mostly in the form of yellow and black bands. There’s also orange, and that varies in an interesting way. The showiest coloration on many bumblebees is an add-on: big showy baskets filled with colorful pollen on the legs of females.
Could it be that a reward for being a busy bee is extra protection? Not all bumblebees have the baskets of orange pollen. Unloaded females don’t, and males don’t. Perhaps some species never do. In any case, some bumblebees have orange fur near where others have baskets of pollen. Fake pollen baskets, that is. Examples include the “Tricolor Bumblebee” and the “Red-Belted BB.”
In other words, as I see it, leg baskets full of orange pollen offer enough protection to be worth “mimicking.” Just to thicken the plot, even fly “wanna-bees” often have orange hips resembling the baskets.