I’ve been writing this blog for a while now, and it’s occurred to me that I’ve never addressed quite a simple and a crucial question. What even are bees? Okay, okay it sounds a bit silly, but… what makes a bee a bee? Wasps are like bees, they buzz, they fly, they sting, but they’re not bees. Of course, you could argue this is just due to humans putting everything into variously labelled boxes. Nevertheless, asking what makes a bee a bee is an interesting question. For example, when you imagine a bee you might think about an insect that lives in a hive and produces honey, but for the vast majority of bee species (>90%) this simply isn’t true. So how would we define a bee?
Google gives you three definitions:
“1. a stinging winged insect which collects nectar and pollen, produces wax and honey, and lives in large communities.
2. an insect of a large group to which the honeybee belongs, including many solitary as well as social kinds.
3. a meeting for communal work or amusement.
“a sewing bee””
Not much help there (although I’m so up for a sewing bee). How about dictionary.com?
Okay… well I struggled to understand that one! Never mind, let’s start with the basics.
Bees are insects
First things first, bees are animals, specifically insects. But why? Biologists have a bunch of categories that we like to put everything into. These are defined by what characteristics the species has. We can safely put bees in the animal category as they can move and also are complex (made of multiple organs and cells). Simple, you’ve never seen many mobile plants after all. So let’s take a look at a bee. Well, they have 6 legs, antennae, compound eyes (essentially eyes that are made up of thousands of tiny eyes), jointed legs, a three part body plan (head, thorax, abdomen) and a chitinous exoskeleton – which makes them sound like an awesome robot, but actually just means they prefer to keep their skeleton on the outside and it’s made of a sugar compound, chitin. So they’re insects. Right, so that’s now narrowed it down to about 6-10 million species.
Within insects there is a group consisting of ants, wasps, sawflies and drumroll… bees. The Hymenoptera. These insects all have two sets of wings that are connected by little hooks called humuli. Some members of this group also has an interesting feature which is a tube-like egg-laying organ, the ovipositor. In many of the Hymenoptera the ovipositor has been converted to a stinger. Now we’re getting somewhere! Bees have stings! But this still doesn’t differentiate them from the rest of the group.
Bees have been around for a really long time, around 130 million years, ~46 times longer than us! We know this because we have found ancient bees trapped in amber (just like in Jurassic park!) that look a lot like modern bees. Also this time-period coincides with an important new development for bees. Flowering plants. It’s probably difficult to imagine a world without flowers, but before 130 million years ago they simply didn’t exist. For a long time, plants had gotten by in their reproduction by just scattering their pollen to the wind and hoping that it would land on a receptive plant. As you can imagine this is a pretty inefficient system to reproduce, it’s the equivalent of going around and asking random strangers to have your babies. One person may say yes, but the chances are extremely low (and they’re probably insane). So in ~130 million BC evolution provided an alternative. Get insects to carry their pollen for them. To do this they had to become attractive, thus flowers!
Now the ancestors of bees are actually wasps. Specifically, their ancestors were Sphecidae wasps, which are wasps that stockpile corpses of insects. Yum. At some point some of these wasps started to stockpile pollen instead. You may think that some bee ancestors simply saw how pretty flowers were and became awash with love and peace and decided to forswear their previous murderous ways. You may be right. We simply don’t know. More likely it could be that they stockpiled insects that were covered in pollen, or by accidentally bringing back pollen as they went about catching insects. However it happened, this was the beginning of bees. Pollen, as it turned out, was a fantastic source of protein, perfect for juvenile growth and ovarian development, excellent things for passing on your genes! Any student of Darwin knows that passing on your genes is what it’s all about (nudge, nudge, wink, wink). To help with their new diet bees became hairier, this and their diet are about the only tangible differences between them and wasps. In the end bees are just vegetarian wasps.