Some 65 million years ago, the first bees, wasps, butterflies and moths appeared on earth. They are the insects that depend on flowers as a source of nutrition during their adult life. From that time onward flowers and certain groups of insects became dependent on one another and therefore contributed to the development of each other.
As the plants developed bright coloured flowers and called attention to the nectar and other food supplies insects developed a taste for the sweet nectar and the nutritious pollen. Prior to this the plants had grown structures that folded over one another to protect the reproductive parts of the plant from hungry pollinators. To overcome the added protection new species of wasps and bees evolved that had strong legs and mouth parts capable of opening the flowers to extract the pollen and nectar.
A flower that attracts only a few kinds of insect visitors and attracts them regularly has an advantage over flowers visited by undependable pollinators. It is an advantage for the insect to have a private food supply that is difficult to get to by insects competing for the same food.
Modern flowers have many distinctive features or special adaptations that encourage regular visits by particular pollinators. The various shapes, colours, and odors allow for sensory recognition by specific pollinators.
Flowers such as orchids, snapdragons and irises with their deep, trumpet-like blooms and unusual landing platforms exclude all but a few desired pollinators; the rest must go away hungry.
Bees pollinate flowers while they are foraging. The anthers deposit pollen grains on the bee’s mid section and when the bee moves to another flower the pollen falls off or is scraped off onto the new flower. Beetles push their way into a flower to get to the nectar or pollen and the sticky pollen clings to their head. When they move to a different flower they take the pollen with them and it brushes off as they search for more food.
The long sucking tongue of a butterfly is able to reach into the flowers of daisy to extract the nectar but in the process collect pollen to be deposited when they visit another flower. Moths are active pollinators as they make their rounds. They, like the butterflies, have long tongues and can sip nectar from deep within the flower’s petals. They collect pollen while they are feeding and spread it to other flowers as they move about.
As hummingbirds collect nectar from a lily or any deep-throated species, pollen collects on the bird’s forehead and is then deposited on the next flower the bird visits. Hummers are particularly good at their job because they will visit many flowers of the same species one after another and this makes sure each flower is pollinated.
Lately there has been a drastic reduction in the numbers of pollinators, mainly bees, and some crop growers must buy hives of bees to pollinate their crops. What is causing the decline is not fully understood which prevents a plan from being developed to solve the problem.
Speaking of Nature
Jim Ferguson, 5313 River Road, R.R.5, Renfrew, Ontario k7V 3Z8 Phone 613-432-2738 email jamesh@nrtco.net
As the plants developed bright coloured flowers and called attention to the nectar and other food supplies insects developed a taste for the sweet nectar and the nutritious pollen. Prior to this the plants had grown structures that folded over one another to protect the reproductive parts of the plant from hungry pollinators. To overcome the added protection new species of wasps and bees evolved that had strong legs and mouth parts capable of opening the flowers to extract the pollen and nectar.
A flower that attracts only a few kinds of insect visitors and attracts them regularly has an advantage over flowers visited by undependable pollinators. It is an advantage for the insect to have a private food supply that is difficult to get to by insects competing for the same food.
Modern flowers have many distinctive features or special adaptations that encourage regular visits by particular pollinators. The various shapes, colours, and odors allow for sensory recognition by specific pollinators.
Flowers such as orchids, snapdragons and irises with their deep, trumpet-like blooms and unusual landing platforms exclude all but a few desired pollinators; the rest must go away hungry.
Bees pollinate flowers while they are foraging. The anthers deposit pollen grains on the bee’s mid section and when the bee moves to another flower the pollen falls off or is scraped off onto the new flower. Beetles push their way into a flower to get to the nectar or pollen and the sticky pollen clings to their head. When they move to a different flower they take the pollen with them and it brushes off as they search for more food.
The long sucking tongue of a butterfly is able to reach into the flowers of daisy to extract the nectar but in the process collect pollen to be deposited when they visit another flower. Moths are active pollinators as they make their rounds. They, like the butterflies, have long tongues and can sip nectar from deep within the flower’s petals. They collect pollen while they are feeding and spread it to other flowers as they move about.
As hummingbirds collect nectar from a lily or any deep-throated species, pollen collects on the bird’s forehead and is then deposited on the next flower the bird visits. Hummers are particularly good at their job because they will visit many flowers of the same species one after another and this makes sure each flower is pollinated.
Lately there has been a drastic reduction in the numbers of pollinators, mainly bees, and some crop growers must buy hives of bees to pollinate their crops. What is causing the decline is not fully understood which prevents a plan from being developed to solve the problem.
Speaking of Nature
Jim Ferguson, 5313 River Road, R.R.5, Renfrew, Ontario k7V 3Z8 Phone 613-432-2738 email jamesh@nrtco.net
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