All seed plants have pollen

Wind or beast?

Plants have come up with a lot in the course of evolution so that their pollen can get to the ovules of a conspecific. Conifers, grasses and many deciduous trees use a more conventional method for this: They simply let the pollen be carried away by the wind. This transports the pollen through the air - until it hopefully lands on the reproductive organ of another plant of the same species.

Wind pollination is the most original form of pollination and is usually quite reliable. But it has a decisive disadvantage: in the individual case, your success is ultimately a matter of chance. In order to increase the chances of reproduction, wind pollinators have to produce huge amounts of pollen. For some people, this flood of pollen has an annoying side effect: it triggers allergies.

Animal helpers

Other plants are more focused on pollination. They recruit animal helpers who carry the pollen from flower to flower. This type of pollination is an invention of angiosperms, also called flowering plants. They often develop showy flowers to attract the attention of their messengers and provide a nutritious reward in the form of nectar. When the animals try to get to the sweet sap in the flower, they brush the stamens of the plant and pollen sticks to their bodies.

In Europe, plants mainly use insects as pollen suppliers - for example bees, butterflies, flies, moths, beetles and wasps. But in other parts of the world, especially in the tropics and subtropics, bats and birds are also frequently active as pollinators.

Flower birds sipping nectar

The most famous and important flower birds are the hummingbirds. Whether the only six centimeters tiny bee elf or the comparatively large giant hummingbird with around 20 centimeters: They are all characterized by an extremely long tongue, the tip of which resembles two half-open straws.

Thanks to a sophisticated pumping mechanism, these trough-shaped reservoirs fill with flower sap in just milliseconds. This technique enables the hummingbirds to fill up with sufficient nectar with their typical lightning-fast licking movements. The birds usually transfer the pollen with their heads.

Mice as pollinators

But busy pollinators are not only found among the flying creatures. Reptiles and non-flightable mammals also serve plants as pollen carriers - for example mice and elephant shrews. The plant Cytinus visseri, which is only found in some regions of South Africa, relies on the pollination work of these animals.

It attracts the small mammals with a seductive scent that magically attracts the animals when they search for food at night. While they lick nectar from the flowers on the ground, pollen clings to their fur, which they shed when they visit the next nectar source.

Daniela Albat
Status: October 20, 2017

20th October 2017