Master of Disguise

By Charlie Whittaker

Boquila trifoliolata is a climbing plant endemic to the swathes of temperate rainforest covering vast areas of South America. Herbivory and grazing is often intense in these areas, and being able to climb away from the prying jaws of potential predators is advantageous for a plant like Boquila trifoliolata. However, one particular attribute separates this clever customer from the other climbing vines found in abundance in rainforest environments. It possesses an extraordinary and unique ability to disguise itself as other plants, altering its development programme to produce different leaf shapes, sizes and textures to match the particular plant is it climbing over. In doing so, it camouflages itself against potential herbivores, blending in with its surroundings and reducing its chance of being eaten.

Whilst mimicry is not a particularly novel concept, having been documented extensively in animals (think stick insects or David Attenborough’s famous Lyrebird capable of imitating a chainsaw) and to an extent in plants, this example is particularly incredible because Trifoliata is able to mimic a multitude of different plants. As well, it is also able to adapt and switch on the fly: the same individual vine can alter its morphology as it traverses different hosts. Following the vine from start to finish then means you could potentially see as many as 5 or 6 different leaf morphologies and structures. Truly a master of disguise.

4210026_origHow Boquila trifoliolata senses which plant it is growing over is still up for debate, but the answer is thought to lie with volatile chemicals that are emitted by many plants. Often indiscernible to you or me, these wind-carried compounds allow plants to communicate: a recent documented example showed that plants release specific compounds when grazed on by a herbivore. These compounds are perceived by other plants in the surrounding area and serve as a warning telling them to upregulate their defences and avoid their compatriot’s mastichatory demise. Though they can be general in purpose and non-species-specific in composition, they needn’t be. Flowers often produce a precise and species-specific cocktail of volatiles in order to attract the right pollinator and ensure dissemination of their pollen.

Coming back to the Boquila trifoliate story then, it is thought the plants trifoliata climbs over each produce their own specific mixture of volatiles. In turn, sensing of these compounds by trifoliate acts as the stimulus to alter its developmental programme, causing different leaf morphologies to be produced. This incredible plant is literally a shapeshifter.

If you want to help a mammoth, buy them flowers….

By Charlie Whittaker

Mammoths have been in the news a lot lately, predominantly due to the recent discovery of a particularly well preserved specimen. There was talk of good condition blood being found, perhaps facilitating the extraction of DNA and the generation of new, 21st century edition woollies.

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A gift for a discerning mammoth?
Credit Jamiesrabbits

But how did they die out in the first place? Everything from climate change, to comet impact, through to human based overhunting have been bandied as reasons for the loss of the majestic mammoth from the face of the earth. But a new study suggests the answer may be a little more mundane than that.

I am, of course, talking about a grass invasion. Anti-climax I know, but consider this: the primary staple of mammoths and other “megafauna” found in that region of the world at the time were broad leafed, flowering plants called “forbs”. This is a diverse family, including tansies and yarrow, and would have represented a key source of protein for the animals.

This all changed about 10,000 years ago: the composition of the flora inhabiting the Arctic shifted substantially, becoming dominated by grasses.

Past studies have failed to pick up this shift, due to their reliance upon pollen analysis. An exceptionally useful marker of flora presence, fossilised pollen found in permafrost or frozen soil can paint a vivid picture of the diversity and makeup of the vegetation inhabiting a region at a given time. This picture can be skewed however, particularly in the case of grasses, which produce huge amounts of pollen and therefore bias the picture of the landscape painted.

This study looked at plant genetic material found in numerous permafrost samples, as well as analysing the DNA found in the guts of fossilised faeces of 8 animals (4 wooly mammoths, 2 wooly rhinoceroses, 1 bison and a horse) that lived in the Arctic during that period.

All of this showed the forbs to be a stable in the diet of these animals: rich in protein and other nutrients, their continued perseverance in the Arctic landscape is thought to have been essential to continued survival of the animals there.

When these disappeared, 10-15,000 years ago, being replaced with comparatively non-nutritious grasses, the animals there were deprived of a staple foodstuff. This is thought to have massively hastened their extinction.

So, if we do eventually resurrect any woolly mammoths, and you want to be kind, then get on their good side and buy them flowers!

Read the full study here.