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  1. I love giving talks to children’s groups because they ask such wonderful questions and I have learnt so much from talking to them.

    One of my favourite questions is, “Where do bees come from?”.  Especially when I can answer that bees were around when the dinosaurs roamed the earth!

    Around 135 million years ago when dinosaurs walked the earth there were also some insects.  Some of these insects were oversized butterflies and dragonflies.

    Plants had been mostly wind pollinated up until this point, but insects and plants had recently discovered a beneficial relationship.  In return for a sugary reward in the form of nectar insects were now pollinating flowers.  Prior to this time flowers were drab greens and browns which blended well with the rest of the vegetation, but they had now started to evolve different colours and shapes to attract the most beneficial insects to pollinate them.

    Flower meadow

    Another group of insects, the wasps, had also evolved.  The term “wasp” usually conjures up images of black and yellow insects being a nuisance at late summer picnics.  There is very much more to wasps then this though.

    Some wasp species catch prey which they feed to their young.  The female wasps stock a nest, often an underground burrow, with the corpses or paralysed bodies of their prey for the young grubs to feed on.  For some reason some of these wasps started to stock their nests with pollen.  It may have been that there was a shortage of their preferred prey, or the pollen may just have been a supplement.  Pollen is very rich in protein (as other insects had discovered) and eventually a wasp species evolved to feed their young solely on pollen and had become the first bees.

    As insects rarely form fossils it is difficult to be precise as to when bees first evolved.  DNA suggests that bees have been around for approximately 130 million years and so were evolving alongside the first flowers.

    Since that time bees and flowers have continued to evolve and diversify side by side. 

    Flowers have adapted various ways and means to attract the bees best adapted to pollinating them, whilst bees have evolved to become specialised nectar and pollen feeders/collectors.  Many species have hairy bodies which trap pollen as they fly from flower to flower. 

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    Others have stiff hairs on their back legs on to which they pack pollen to transfer it back to their nests. Common carder

    Some have evolved longer and longer tongues with which to reach nectar, and so the variations go on.

    Today there are approximately 25,000 known species of bee worldwide.

    In the UK we have around 280 different bees.  1 of these is the honey bee, 27 are bumble bees and the rest are solitary bees.

    And the wasps?  Well they evolved too . . .

    Ruby tailed wasp - bee tubes (2)

  2. A gloomy January morning walk today had me thinking about how very different our world could have been without insects. 

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    When we think of nature and conservation we tend to think of the larger animals and birds, but insects really are the invisible unsung heroes of our world.

    Around 135 million years ago, dinosaurs walked the earth.  When we think of dinosaurs roaming the earth, we tend to think of huge beasts tearing up the vegetation, colossal battles between gigantic armour plated warriors, and herds of smaller beasts being chased and preyed upon by larger dinosaurs, whilst the gigantic forerunners of today’s birds dominate the skies.

    We rarely, if at all, give much thought to the plants and insects which would have inhabited this world.

    fern

    Plant life was a mixture of greens.  Plant pollination would have relied on the wind (or large clumsy beasts brushing against them to dislodge the pollen).  Some plants today are still mostly wind pollinated but this is a very haphazard method of pollination.  The male parts of the plant produce pollen which is, hopefully, blown on to the female part of a nearby plant.  This method of pollination relies a lot on chance, and vast quantities of pollen must be produced for successful pollination.

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    Amongst the vegetation were insects, including oversized butterflies and dragonflies.  Some of the winged insects started to feed on pollen.  As they flew from plant to plant feeding some of the pollen became trapped in their hairs or joints and was dropped on neighbouring plants.

    Much less pollen was needed for successful pollination by insects.  To begin with insects would have had to search for the insignificant green and brown flowers, but as pollination by insects was much more reliable plants responded by evolving ways to attract more insects.  Where before everything had been green, now the first flowers started to appear.

    Apple blossom (5)

    Petals helped to advertise where the pollen on a plant could be found, and if those petals were white rather than green they stood out against the background of green plants.  These plants would have been much more successful at attracting insects and so more and more diversification took place. 

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    Some plants also responded by starting to produce nectar – a sweet, sugary reward in return for pollination.  As nectar producing is hard work for plants, plants evolved to attract the insects which were best able to pollinate them.  Different colours emerged, alongside different flower shapes.  Some plants developed long tubes with the nectar at the base, some butterflies responded by evolving long tubular tongues to suck up this nectar. 

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    Others developed patterns to advertise where the nectar could be found.

    The most successful group of insects to emerge during this period were the bees.  Today much of our flora relies mostly on the pollination services of our bees.  Its hard to imagine how our world would have looked with out flowers.

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