Flower Power - Sex, Flies & Videotape - How to Grow a Planet BBC Two

BBC Two, Tues 14th February at 9pm on BBC 2.

Read Nigel's first hand account, video & images, filming the worlds biggest caves

The nuts & bolts of flower sex

As recently as 130 million years ago plant life was so limited in its evolutionary journey that the part of a plant we prize above all else – didn’t exist at all. It is the flower. What’s even more surprising is that in the geologically short time they've been around flowers have brought about the single most powerful transformation in our planet’s history. They kick started an explosion of diversification in the animal kingdom – that ultimately lead to us, humans.

It begins with a sexual revolution.

All organisms have to reproduce to survive – that’s what a flower is for. Iain begins by getting to grips with the nuts and bolts of plant sex – to discover why flowering plants were so much more successful than the ancient rulers of the plant kingdom – the conifers and ferns.

"The older ferns and conifers relied on something completely random - wind and water – its amazing they worked at all. But everything in history changed with flowers – they’re basically super-efficient sex organs! Then by forming all kinds of incredible partnerships with animals, flowers just rampantly take over the world, transforming the planet and helping steer evolution of animals as they go."- Nigel Walk, Director & Producer

A botanical time-capsule

Iain travels to the remote South Pacific Island of New Caledonia to track down the oldest surviving relatives of one of the first plants to evolve flowers… the incredibly rare Amborella trichopoda.
New Caledonia is a botanical time-capsule – like stepping back in time over 140 million years to a world before flowers even existed. This exotic island is so distant and cut off from the rest of the continents that many types of ancient plants still thrive where elsewhere they have died out… It’s the only place in the world Amborella grows in the wild.

The flowers of Amborella trichopoda, New Caledonia Wiki Source

"It was very touch and go whether we’d even find one of these rare plants" said Nigel "obviously they only flower for certain times of the year and we wanted to film them growing wild and not in a botanical garden. We had teams of botanists exploring the rainforest for us trying to track them down. We were on standby right up until the day we flew out."

Scientists still don’t know exactly how and why flowers appeared – there’s some evidence they share genes with fir cones, or evolved from adapted leaf structures. What's remarkable is that flower fossils all start appearing around the same time – 140 – 130 million years ago. Darwin called this an ‘abominable mystery’ – why did they suddenly appear, in a geological blink of an eye.

Seeds survive being shot

The appearance of all this 'flower power' is set in the context of an ancient planet that was being reshaped by geological forces. The ancient mega-continent of Pangaea was breaking up and new habitats and niches were being formed. Iain explores how flowering plants, perhaps above all plants, had a survival ‘toolkit’ that made them better adapted to colonise a changing planet.

To demonstrate just how tough some flowering plants can be Iain uses a shotgun to fire seeds through wood! Seeds are fantastic time capsules for plants. Many survive being eaten by animals, being buried or even burnt. They are able to lie dormant for many years, waiting until the conditions are favourable for the plants to grow.

Flies, Bees & Beetles - Harnessing the power of animals

Above all, the reason why flowers were so successful was because they harnessed animals to reproduce – flies, beetles, bees. It’s the biggest case of ‘I’ll scratch your back if you scratch mine’!

Bees are the most important flower pollinators, they evolved from carnivorous wasps that had turned their backs on meat in favour of pollen and nectar. As they evolved they became perfectly adapted to collect pollen from flowers. Their whole bodies became covered in hair, so that the pollen would stick when they landed on flowers. They developed special antennae to smell out nectar and their sophisticated compound eyes, each made up of up to 6000 tiny lenses, were prefect at spotting flowers. They can also see UV markings on plants - patterns that are indetectable to the human eye. 

"One of the hallmarks of the series, that we’ve not seen before is the specially shot HD microscopy. A lot of microscopy just looks like a sample in a lab, but in this series we’ve been able to shoot footage of a bee eye on a living bee, for example, or the inner workings of a living flower – to show spectacular colourful detail, to move around the plant in real time. It’s like the movie ‘Inner Space!"

Petals – adverts for flowers

 

Click here to read Nigel Walk's first hand account, with video and images, of the worlds biggest caves - Han Song Doong in Vietnam.