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Arctic whale populations may be soaring
In this section n Nuclear bunker ant colony, page 8 n The Great Green Wall, page 16 n Putting your data to work for you, page 22
Create a better universe to make life more likely
Arctic whale populations may be soaring IT’S boom time for large whales in the Arctic – an unexpected benefit of the unprecedented sea ice reduction seen in the region over the past 30 years. Sue Moore at the National Oceanic and Atmospheric Administration in Seattle has analysed 30 years of whale survey information gathered in the Chukchi Sea – which separates Russia and Alaska – and the
“The natural stepping stone towards bigger elements is not present,” says Adams. That’s no way to build a cosmos – yet strangely, here we are. In the 1950s, astronomer Fred Hoyle figured out a solution. He argued that the abundance of carbon in the universe must be the result of a coincidence between the energy levels of alpha particles and carbon-12. Hoyle said that because the energy of three alpha particles creates carbon-12 with more energy than it needs to be stable,
NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
YOUR existence depends on an improbable threesome: a delicate reaction within stars called the triple-alpha process, which creates carbon. This is often used to support the idea of the multiverse. But stars in other universes might have alternative ways of producing carbon, giving life as we know it a greater chance in multiple universes. At least, that’s the view of Fred Adams at the University of Michigan in Ann Arbor and his colleague Evan Grohs. The triple-alpha process gets its name from the three helium nuclei involved, also known as alpha particles. When the universe formed, it mostly consisted of hydrogen and helium, the simplest elements in the periodic table. Heavier elements were forged by the first stars, which fused the lighter nuclei together. There’s just one problem with this tidy model. Fuse two alpha particles and you end up with a nucleus of four protons and four neutrons – namely beryllium-8. But this isotope is highly unstable and falls apart into two alpha particles within a fraction of a second. That means there isn’t much of it in our universe.
this extra energy must be equal to an excited state of carbon-12, allowing it to decay to its ground state and remain stable. This socalled “resonance” between the energy values makes it possible to form carbon by fusing three alpha particles together. Experiments later proved him right, but vary the energy levels slightly and no carbon is produced at all. Hoyle and others argued that this means our universe must have been fine-tuned for life. That resonance could have occurred at a range of energies, and the fact that it just happened to take place at the crucial point for us to exist makes us astonishingly lucky. The odds of this happening at
random are very low, and some argue that the only way to explain it is if our universe is just one of many in a multiverse. In that case, each universe could have slightly different values for the fundamental constants of physics. Life would arise only in suitable universes, meaning we shouldn’t be surprised to find ourselves in one of these. But now Adams and Grohs argue that if other universes have different fundamental constants anyway, it’s possible to create a universe in which beryllium-8 is stable, thus making it easy to form carbon and the heavier elements. For this to happen, a change in the binding energy of beryllium-8 of less than 0.1 megaelectronvolts would be required – something that should be possible by slightly altering the strength of the strong force, which is responsible for holding nuclei together. Simulating how stars might burn in such a universe, they found that the stable beryllium-8 would create an abundance of carbon, meaning life as we know it could potentially arise. These alternate universes would arguably be more logical, he says, with stars steadily building elements along the periodic table without having to resort to the triple-alpha process. “In some sense, we’ve designed a better universe,” says Adams.
–Life, but more logical than ours– Jacob Aron n
surrounding area. She realised that three species of plankton-eating baleen whales – humpback, fin and minke – are now routinely spotted in the region, even though surveys in the 1980s never encountered these species there. The population of bowheads – a baleen whale native to the Arctic – may also be thriving, according to Moore’s analysis (Biology Letters, DOI: 10.1098/rsbl.2016.0251). This rise in whale sightings coincides with melting sea ice. “Millions of square miles of sea ice has been lost in the past decade,”
says Marc Macias-Fauria at the University of Oxford. The lack of ice leads to extraordinarily favourable growing conditions for zooplankton – which is a good thing for the baleen whales that eat them, says Patrick Miller at the University of St Andrews in the UK. More light can penetrate into the surface water of ice-free oceans, fuelling blooms of phytoplankton and
“A lack of ice leads to favourable conditions for zooplankton – great for the whales that eat them”
the zooplankton that graze on them. Nutrient levels also increase. “Wind driven across the now open sea surface causes water to mix,” says Miller. “This brings nutrients up from depth.” Some believe the Arctic has entered a “new normal” in which there is permanently less sea ice. But this might ultimately create more problems for the whales. This is because the ice-free waters are attracting more human attention – and the noise from our marine activities may have a detrimental impact on Arctic whale populations in the longer term. Laura Hampton n 10 September 2016 | NewScientist | 7
Create a better universe to make life more likely
Arctic whale populations may be soaring IT’S boom time for large whales in the Arctic – an unexpected benefit of the unprecedented sea ice reduction seen in the region over the past 30 years. Sue Moore at the National Oceanic and Atmospheric Administration in Seattle has analysed 30 years of whale survey information gathered in the Chukchi Sea – which separates Russia and Alaska – and the
“The natural stepping stone towards bigger elements is not present,” says Adams. That’s no way to build a cosmos – yet strangely, here we are. In the 1950s, astronomer Fred Hoyle figured out a solution. He argued that the abundance of carbon in the universe must be the result of a coincidence between the energy levels of alpha particles and carbon-12. Hoyle said that because the energy of three alpha particles creates carbon-12 with more energy than it needs to be stable,
NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
YOUR existence depends on an improbable threesome: a delicate reaction within stars called the triple-alpha process, which creates carbon. This is often used to support the idea of the multiverse. But stars in other universes might have alternative ways of producing carbon, giving life as we know it a greater chance in multiple universes. At least, that’s the view of Fred Adams at the University of Michigan in Ann Arbor and his colleague Evan Grohs. The triple-alpha process gets its name from the three helium nuclei involved, also known as alpha particles. When the universe formed, it mostly consisted of hydrogen and helium, the simplest elements in the periodic table. Heavier elements were forged by the first stars, which fused the lighter nuclei together. There’s just one problem with this tidy model. Fuse two alpha particles and you end up with a nucleus of four protons and four neutrons – namely beryllium-8. But this isotope is highly unstable and falls apart into two alpha particles within a fraction of a second. That means there isn’t much of it in our universe.
this extra energy must be equal to an excited state of carbon-12, allowing it to decay to its ground state and remain stable. This socalled “resonance” between the energy values makes it possible to form carbon by fusing three alpha particles together. Experiments later proved him right, but vary the energy levels slightly and no carbon is produced at all. Hoyle and others argued that this means our universe must have been fine-tuned for life. That resonance could have occurred at a range of energies, and the fact that it just happened to take place at the crucial point for us to exist makes us astonishingly lucky. The odds of this happening at
random are very low, and some argue that the only way to explain it is if our universe is just one of many in a multiverse. In that case, each universe could have slightly different values for the fundamental constants of physics. Life would arise only in suitable universes, meaning we shouldn’t be surprised to find ourselves in one of these. But now Adams and Grohs argue that if other universes have different fundamental constants anyway, it’s possible to create a universe in which beryllium-8 is stable, thus making it easy to form carbon and the heavier elements. For this to happen, a change in the binding energy of beryllium-8 of less than 0.1 megaelectronvolts would be required – something that should be possible by slightly altering the strength of the strong force, which is responsible for holding nuclei together. Simulating how stars might burn in such a universe, they found that the stable beryllium-8 would create an abundance of carbon, meaning life as we know it could potentially arise. These alternate universes would arguably be more logical, he says, with stars steadily building elements along the periodic table without having to resort to the triple-alpha process. “In some sense, we’ve designed a better universe,” says Adams.
–Life, but more logical than ours– Jacob Aron n
surrounding area. She realised that three species of plankton-eating baleen whales – humpback, fin and minke – are now routinely spotted in the region, even though surveys in the 1980s never encountered these species there. The population of bowheads – a baleen whale native to the Arctic – may also be thriving, according to Moore’s analysis (Biology Letters, DOI: 10.1098/rsbl.2016.0251). This rise in whale sightings coincides with melting sea ice. “Millions of square miles of sea ice has been lost in the past decade,”
says Marc Macias-Fauria at the University of Oxford. The lack of ice leads to extraordinarily favourable growing conditions for zooplankton – which is a good thing for the baleen whales that eat them, says Patrick Miller at the University of St Andrews in the UK. More light can penetrate into the surface water of ice-free oceans, fuelling blooms of phytoplankton and
“A lack of ice leads to favourable conditions for zooplankton – great for the whales that eat them”
the zooplankton that graze on them. Nutrient levels also increase. “Wind driven across the now open sea surface causes water to mix,” says Miller. “This brings nutrients up from depth.” Some believe the Arctic has entered a “new normal” in which there is permanently less sea ice. But this might ultimately create more problems for the whales. This is because the ice-free waters are attracting more human attention – and the noise from our marine activities may have a detrimental impact on Arctic whale populations in the longer term. Laura Hampton n 10 September 2016 | NewScientist | 7