From my understanding:
I get that for honeybees, they need the nectar to make honey (their energy food source) and the pollen is an additional, essential food source for them which contains protein. They collect both nectar and pollen from flowers.
For other pollinators like wasps, they don't make honey but they still need to eat nectar and pollen which they collect from flowers.
Though these pollinators benefit (survive/thrive) by collecting nectar and pollen from flowers, they also help plants to reproduce by carrying pollen between them and depositing it.
But why do they transfer pollen to other flowering plants? Of course this allows certain plants to reproduce, but that doesn't explain why these pollinators care about helping plants reproduce. Are they little plant farmers who actually realise that transferring pollen and therefore making more plants, would benefit them? That would seem to demonstrate pretty high-level intelligence and foresight, planning wouldn't it? Or is it just incidental that they're going between flowers collecting nectar and pollen and happen to drop some pollen from previous flowers along the way?
I really struggled to find any information on the "WHY" of what bees are doing, from their own psychology point of view.
Bees make excellent pollinators because most of their life is spent collecting pollen, a source of protein that they feed to their developing offspring. When a bee lands on a flower, the hairs all over the bees' body attract pollen grains through electrostatic forces.
Basically plants have coevolved with these pollinating insects. Plants that can develop the best pollen that sticks to these insects are able to reproduce more successfully. While bees, as the example, are collecting it as there food. Bees are not "helping" the plant knowingly, its more of the plant is hitching a ride.
So, the plants found a way to hijack the bees' journey by putting some extra pollen on them to take to other flowers, since they're already there taking pollen anyway? That's awesome.
The flowers are also evolving to spread pollen to reproduce. Flowers have evolved to be bright, colorful and have pollen that bees want. Flowers are able to get there pollen spread and bees get food.
Possibly when furrier bees evolved, it could be that the fur was protecting them from harsh weather conditions and allowing them to fly further and making it to more flowers. The fur builds electrostatic forces as the bee went along with its day. Serving another beneficail purpose by attracting more pollen to stick onto their bodies. The bees also use the fur to wipe pollen from their eyes and off their legs.
Essentially furrier bees were more successful at feeding their offspring than non-fur bees. Which was selecting for even furrier bees in the following generations continuing to the furry honeybees we see today.
Ha I was writing another comment on this thread when this got posted, but I just feel like it's important, relevant to that, to say that the hairs didn't evolve FOR any specific purpose.
Well said. Evolution doesn't have a goal. I ran into the difficulty when teaching is that students tended to assign purpose to mutations that are currently beneficial.