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  • Bees are very busy little matchmakers.

  • Wingmen in every sense of the word.

  • You see, the bees' side of the whole "birds and the bees" business is to help plants find mates and reproduce.

  • In their work as pollinators, honeybees are integral to the production of nearly 1/3 of the food that we eat.

  • And these bees, dutifully helping lonely plants have sex, aren't alone.

  • But rather are part of a very complex network of matchmaking creatures, critical for the pollination of natural ecosystems and crops.

  • Plants in many natural ecosystems need help to have sex.

  • Like many of us, they're too busy to find a relationship.

  • They have too much photosynthesis to do, and they can't find the time to evolve feet and walk to a singles bar.

  • Those places are called meat markets for a reason, because plants can't walk.

  • So they need matchmaker pollinators to transport their pollen grains to flowers of the same plant species.

  • And they pay these pollinators with food.

  • Today, around 170,000 plant species receive pollination services from more than 200,000 pollinator species.

  • Pollinators include many species of bees, butterflies, moths, flies, wasps, beetles, even birds and bats,

  • who together help pollinate many species of trees, shrubs and other flowering plants.

  • In return, flowering plants are an abundant and diverse food source for pollinators.

  • For instance, fossil records suggest bees may have evolved from wasps that gave up hunting after they acquired a taste for nectar.

  • Plant pollinator networks are everywhere.

  • Ecologists record these networks in the field by observing which pollinators visit which plants, or by analyzing the identity of pollen loads on their bodies.

  • Networks, registered in these ways, contain from 20 to 800 species.

  • These networks show a repeated structure, or architecture.

  • Pollinators interact with plants in a very heterogeneous way.

  • Most plants are specialists, they have only one or a few matchmakers.

  • Meanwhile, only a few generalist plants hire a diverse team of matchmakers, getting visits from almost all the pollinators of the network.

  • The same occurs with pollinators.

  • Most are specialists that feed on only a few plant species, while a few pollinators, including the honeybee usually, are generalists, busily feeding from and matchmaking for almost all the plant species in that ecosystem.

  • What's interesting is that specialists and generalists across both plants and pollinators, sort themselves out in a particular pattern.

  • Most pollinator networks, for which we have data, are nested.

  • In a nested network, specialists tend to interact more with generalists than with other specialists.

  • This is because if you're a specialist plant, and your only matchmaker also specializes on you as its only food source, you're each more vulnerable to extinction.

  • So, you're better off specializing on a generalist pollinator that has other sources of food to ensure its persistence in bad years.

  • The same goes if you're a specialist pollinator.

  • You're better off in the long run specializing on a generalist plant that gets pollinated by other species in times when you're not around to help.

  • Finally, in addition to nestedness, the networks are usually modular.

  • This means that the species in a network are compartmentalized into modules of plants and animals that interact more with each other than with species in other modules.

  • Think of them like social cliques.

  • A plant or pollinator dying off will effect the species in its module.

  • But those effects will be less severe on the rest of the network.

  • Why's all that important?

  • Because plant pollinator network structure affects the stability of ecosystems.

  • Heterogeneous distribution, nestedness and modularity enable networks to better prevent and respond to extinctions.

  • That's critical because nature is never static.

  • Some species may not show up every year.

  • Plants flower at different times.

  • Pollinators mature on varying schedules.

  • Generalist pollinators have to adapt their preferences depending on who's flowering when.

  • So from one flowering season to the next, the participants and patterns of matchmaking can drastically change.

  • With all those variables, you can understand the importance of generalist pollinators, like bees, to the stability of not only a crop harvest, but the entire network of plants and pollinators we see in nature, and rely on for life.

  • Next time you see a bee fly by, remember that it belongs to a complex network of matchmakers critical to the love lives of plants all around you.

Bees are very busy little matchmakers.

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B2 TED-Ed plant network flowering interact pollination

【TED-Ed】How bees help plants have sex - Fernanda S. Valdovinos

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    小爸 posted on 2019/06/11
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