Flowers are plants’ reproductive organs. The basics of the design haven’t changed much since the first flowering plants evolved, somewhere between 140 and 250 million years ago. At the heart of a whorl of petals lie the stamens, which produce pollen, and the pistils, which contain ovules – when pollen meets ovules, fertilisation can occur, producing seeds which will in turn grow the next generation of plants.
Within that basic scheme, however, lies a world of variation: there are almost 300,000 known species of flowering plants, or angiosperms. Below are a handful of the most visually striking.
Orchis simia, an orchid found around the Mediterranean and in central Asia and parts of the middle east and northern Africa, is one of several species known as “monkey orchid”. The reason for the name is not hard to discern: the purplish blooms look quite a lot like monkeys.
All orchid flowers are bilaterally symmetric – the left-hand side is a mirror image of the right – and many of them have evolved complex shapes to lure insects to help with pollination.
Rafflesia keithii (sometimes known as the corpse flower) is a parasitic plant that grows only in Sabah on the island of Borneo. The plant has no stems, leaves or roots: it latches onto certain vines for its nourishment, and produces enormous blooms (up to 1 metre in diameter) on the forest floor. Like other plants of the Rafflesia genus, it attracts pollinating insect by producing a scent like rotting meat.
On the other side of the world, the only distantly related Hydnora africana practices some of the same tricks as R. keithii. Found throughout southern Africa, it too is a parasite, unable to photosynthesise, so it relies on siphoning off nutrients from other plants below the ground. After rainfall, it extends a flower up to bring in pollinating insects. Once the insects enter the flower, it closes for a couple of days to ensure thorough pollination, before opening to release them. Hydnora africana also produces a strong unpleasant odour to bring in the crowds: rather than a dead animal, however, it is more often compared to faeces.
While R. keithii and H. africana should be kept a long way from any inhabited area, our next flower is prized (by humans) for its scent as well as its appearance. Beehive ginger (Zingiber spectabile) is native to the islands of southeast Asia. Its flowers sit atop a complex supporting structure known as a bract that resembles a beehive, and give off a pleasant gingery smell.
Sturt’s desert pea
Sturt’s desert pea (Swainsona formosa) is a striking wildflower found across the arid parts of central and northwestern Australia. Though the physical resemblance is hard to see, S. formosa is a member of the pea family, producing as fruit a legume, each one containing 50 or more flat, kidney-shaped seeds.
Snapdragon seed pod
After flowering, a plant’s ovaries (if fertilised) form fruit, containing seeds. Not all fruit are edible, like apples or melons. The fruit of the snapdragon (Antirrhinum majus) – named for its handsome flower that somewhat resembles a dragon’s face with a mouth that opens and closes when squeezed – is the seed pod shown above.
With the seeds gone, the pod bears a strange resemblance to a human skull.
Michael Lucy is features editor of Cosmos.
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