News reports insistently tell us that bees pollinate one-third of the world’s food supply. But what does that really mean?
First of all, that estimate varies with the researcher, but it usually includes all animal-pollinated crops, not just those pollinated by bees. These animal pollinators include many types of insects as well as birds and bats. Nevertheless, some folks estimate that bees are responsible for about 75% of all animal pollination. But again, the numbers vary.
Secondly, the “one-third” estimate usually includes that portion of the meat supply that was fed animal-pollinated crops, such as alfalfa and clover. This is another number that is hard to calculate because, in modern agriculture, more and more animals are fed grains instead of leafy forage.
The two-thirds of the food supply not pollinated by animals is dominated by the grains. Most grains are in the grass family and are normally pollinated by the wind. They include wheat, corn, millet, rice, rye, barley, oats, spelt, sorghum, and lesser known crops such as teff and triticale. Quinoa and amaranth are two non-grass grains that also require no animal pollinators. The two-thirds portion also includes crops that could be pollinated by animals, but are not, such as potatoes. (Nearly all potatoes are propagated by seed pieces, which are not seeds at all but chunks of potato that sprout when planted.) Lastly, the two-thirds includes fish, and that amount of meat which is raised on grain or other crops not pollinated by animals.
So why are animal-pollinated plants so important? The grains and meat can supply all the calories, protein, and fat we could possibly use, but the flowering plants provide the vast array of vitamins, minerals, phytochemicals, flavonoids, antioxidants, and trace elements that we need for good health. We could not survive in a world devoid of the animal-pollinated plants, so caring for pollinators is not a choice but a necessity.
I am glad you bring up the different estimates. No matter how you look at it, pollinators clearly are very important, but it is always good to understand what is behind the numbers. While researching for our project, we keep being puzzled by another question, though: what exactly does “one third” refer to? One third of the volume? One third of the value? One third of the calories? Since we are comparing grains with fruit with meat the actual amounts behind that could vary greatly. Any idea?
Great question. It might take me a day or so, but somewhere I have the paper in which that number was first calculated. I’ll try to find it. It seems to me the author was talking about calories, but that doesn’t seem right. It would take a lot of zucchini to compete calorie-wise with something like corn.
As you know, these numbers get tossed around with no thought to units. It drives me crazy. I’ll try to get to the bottom of it. Thanks so much for your comment. Try to be patient, though, my masters thesis is coming due . . .
No worries, that answer sure is worth waiting for.
Good luck with your thesis!
Good article. About potatoes, 1) wouldn’t they need to be cross-pollinated (by insects) at least every now and then, and grown from seed, to keep them healthy and increase genetic variety? 2) Do non-pollinated potatoes grow the same amount/ same quality of potatoes compared to pollinated potatoes? I would assume that crops increase thanks to being pollinated, as do self-pollinating plants like peas and beans, but I can’t find any conclusive information about it.
Well, Anneke, if you have never grown potatoes from seed you are missing one of life’s little pleasures. Usually you can just let your potatoes go to seed and then harvest them. The fruits look like small tomatoes that stay green. Some varieties of potatoes seed easier than others, but I always get some. Of course, no telling what you’ll get from planting them, but it won’t be like the parents.
Anyway, your questions:
1. Yes. TPS (true potato seed) is used in breeding.
2. TPS usually produces smaller and more variable potatoes, but sometimes you can find a trait you are looking for and use it to breed a certain quality into other stock.
3. See “What is incomplete pollination?“
This is an old blog post, but thought it worthwhile to share that our 2018 Southwestern Ohio Beekeeper School is offering a Pollinator Advocate Training. I immediately thought of you when I saw it in the brochure. If I was not a 4-month-old new beekeeper needing and wanting to learn options on better care of my hives, I may have taken these to learn more about all the different pollinators!
Pollinator Advocate Training…that sounds so interesting. Thank you.