Flowering plants first emerged 140 million years ago, during the Cretaceous, a geological time period when dinosaurs roamed the earth and forests stretched to the iceless poles. The first flowers had no nectar but did have pollen. Insects such as beetles fed on this, pollinating as they went.
Flowers began to diversify in colour and shape, and then to offer rewards such as nectar to their pollinators. Predatory wasps, who fed the pollen-covered beetles to their larvae, began cutting out the beetles to feed directly on the nectar itself.
Over time, bees and flowers co-evolved, the bees adapting to carry more nectar, flowers forming longer nectar tubes and the bees longer tongues. Eventually, what we know as modern bees evolved, pollinating ever more diverse flowering plants.
