Water horses: a mother and baby hippo swim at a zoo in Mexico City. Photo: Getty
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Michael Brooks: Hippo fossils offer clues about swimming

Fossilised guides to what the earth was like millions of years ago are rare, and understanding water tracks can make a difference.

Swimming is unlikely to be something you think about in scientific terms. If you’re doing it at the beach, it’s meant to be fun. And if you’re at a pool, it’s relaxing, or part of an exercise routine. To many scientists, though, swimming is an aide to understanding our place in the world.

Three British scientists have just published their observations of hippopotamus swimming. And not by any old hippo – they were interested in the swimming style of a now-extinct species called Hippopotamus gorgops.

Their interest was piqued by some peculiar tracks in what was once a small lake in northern Kenya. The tracks suggest that 1.4 million years ago a hippo had pushed itself off from the edge, before half walking and half swimming across the lake. It would have been the first observation of fossilised swim tracks made by mammals, so the scientists went to watch modern hippos swimming in a shallow pool to see whether the tracks made sense. They did: the observed hippos paddled through a pool, leaving similar hoof marks on the bottom.

Fossilised guides to what the earth was like millions of years ago are rare. We have to take advantage of every available clue, and understanding water tracks can make a difference. Last year, fossilised tracks that had been associated with a dinosaur stampede were reinterpreted as a river crossing.

We are unlikely ever to find out exactly how land-based dinosaurs swam, but it’s a good bet they looked nothing like we do in the pool. Most four-limbed land creatures swim doggy-paddle. When researchers took chimps and orang-utans for a swim, however, they found breaststroke was the natural instinct for staying afloat. It is probably easier for creatures built with shoulders and hips which have evolved to reach for branches to move limbs parallel to the surface of the water.

Not that our fastest swimmers use breaststroke any more. The front crawl has been in human use for thousands of years, but our observations of the natural world have made it even more efficient. Watching the swimming events at the Commonwealth Games, you’ll see several tricks copied from more natural swimmers.

At the turn, for instance, the competitors will empty their lungs, making them less buoyant. Doing this enables them to use their energy to move forward rather than maintain depth, which is why marine mammals and birds exhale deeply before diving into water.

It is important to remain streamlined when under water, so the leg kick has to be kept to no more than one-third of the body’s length – which is how much the dolphin’s tail moves naturally. Competitors are allowed to swim no more than 15 metres of each length under water and they will make the most of this, as the water there offers one-fifth the resistance of the drag just beneath the surface, research shows.

Swimmers can gain an advantage by mimicking penguins’ and dolphins’ streamlined shape and smooth surface. Hence, swimsuits are engineered to hold the human body in an optimum shape and to allow water to move past with minimal resistance.

That said, you can’t mimic everything in nature. Studies of the clawed frog showed the importance of a long push-off from the end of the pool: its pelvis actually slides along its backbone to give extra length to its legs. But not even the Olympic champion Michael Phelps could manage that. 

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

This article first appeared in the 23 July 2014 issue of the New Statesman, Summer Double 2014

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The Autumn Statement proved it – we need a real alternative to austerity, now

Theresa May’s Tories have missed their chance to rescue the British economy.

After six wasted years of failed Conservative austerity measures, Philip Hammond had the opportunity last month in the Autumn Statement to change course and put in place the economic policies that would deliver greater prosperity, and make sure it was fairly shared.

Instead, he chose to continue with cuts to public services and in-work benefits while failing to deliver the scale of investment needed to secure future prosperity. The sense of betrayal is palpable.

The headline figures are grim. An analysis by the Institute for Fiscal Studies shows that real wages will not recover their 2008 levels even after 2020. The Tories are overseeing a lost decade in earnings that is, in the words Paul Johnson, the director of the IFS, “dreadful” and unprecedented in modern British history.

Meanwhile, the Treasury’s own analysis shows the cuts falling hardest on the poorest 30 per cent of the population. The Office for Budget Responsibility has reported that it expects a £122bn worsening in the public finances over the next five years. Of this, less than half – £59bn – is due to the Tories’ shambolic handling of Brexit. Most of the rest is thanks to their mishandling of the domestic economy.

 

Time to invest

The Tories may think that those people who are “just about managing” are an electoral demographic, but for Labour they are our friends, neighbours and the people we represent. People in all walks of life needed something better from this government, but the Autumn Statement was a betrayal of the hopes that they tried to raise beforehand.

Because the Tories cut when they should have invested, we now have a fundamentally weak economy that is unprepared for the challenges of Brexit. Low investment has meant that instead of installing new machinery, or building the new infrastructure that would support productive high-wage jobs, we have an economy that is more and more dependent on low-productivity, low-paid work. Every hour worked in the US, Germany or France produces on average a third more than an hour of work here.

Labour has different priorities. We will deliver the necessary investment in infrastructure and research funding, and back it up with an industrial strategy that can sustain well-paid, secure jobs in the industries of the future such as renewables. We will fight for Britain’s continued tariff-free access to the single market. We will reverse the tax giveaways to the mega-rich and the giant companies, instead using the money to make sure the NHS and our education system are properly funded. In 2020 we will introduce a real living wage, expected to be £10 an hour, to make sure every job pays a wage you can actually live on. And we will rebuild and transform our economy so no one and no community is left behind.

 

May’s missing alternative

This week, the Bank of England governor, Mark Carney, gave an important speech in which he hit the proverbial nail on the head. He was completely right to point out that societies need to redistribute the gains from trade and technology, and to educate and empower their citizens. We are going through a lost decade of earnings growth, as Carney highlights, and the crisis of productivity will not be solved without major government investment, backed up by an industrial strategy that can deliver growth.

Labour in government is committed to tackling the challenges of rising inequality, low wage growth, and driving up Britain’s productivity growth. But it is becoming clearer each day since Theresa May became Prime Minister that she, like her predecessor, has no credible solutions to the challenges our economy faces.

 

Crisis in Italy

The Italian people have decisively rejected the changes to their constitution proposed by Prime Minister Matteo Renzi, with nearly 60 per cent voting No. The Italian economy has not grown for close to two decades. A succession of governments has attempted to introduce free-market policies, including slashing pensions and undermining rights at work, but these have had little impact.

Renzi wanted extra powers to push through more free-market reforms, but he has now resigned after encountering opposition from across the Italian political spectrum. The absence of growth has left Italian banks with €360bn of loans that are not being repaid. Usually, these debts would be written off, but Italian banks lack the reserves to be able to absorb the losses. They need outside assistance to survive.

 

Bail in or bail out

The oldest bank in the world, Monte dei Paschi di Siena, needs €5bn before the end of the year if it is to avoid collapse. Renzi had arranged a financing deal but this is now under threat. Under new EU rules, governments are not allowed to bail out banks, like in the 2008 crisis. This is intended to protect taxpayers. Instead, bank investors are supposed to take a loss through a “bail-in”.

Unusually, however, Italian bank investors are not only big financial institutions such as insurance companies, but ordinary households. One-third of all Italian bank bonds are held by households, so a bail-in would hit them hard. And should Italy’s banks fail, the danger is that investors will pull money out of banks across Europe, causing further failures. British banks have been reducing their investments in Italy, but concerned UK regulators have asked recently for details of their exposure.

John McDonnell is the shadow chancellor


John McDonnell is Labour MP for Hayes and Harlington and has been shadow chancellor since September 2015. 

This article first appeared in the 08 December 2016 issue of the New Statesman, Brexit to Trump