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Is Intelligence Out There?

alien

Is human-like intelligence too much to expect?

By Stephen Luntz

Intelligence may not be the ultimate outcome of evolution on Earth, so why should we expect human-like intelligence elsewhere in the cosmos?

Dr Charlie Lineweaver has presented a new take on the question of whether we are alone in the universe. He argues that the chance we will ever encounter an alien species with “human-like” intelligence is vanishingly small. To expect anything else is a form of arrogance, he believes.

The Rise of the Crocodile Hunters

The skull of Australopithecus sediba from Malapa in South Africa.

The skull of Australopithecus sediba from Malapa in South Africa. Photo by Brett Eloff courtesy Lee Berger

By Andy Herries

Recent excavations in Kenya have revealed the first evidence that a diet of fish and crocodiles two million years ago may have aided the development of larger brains in the human lineage.

The oldest evidence of human cultural remains, in the form of stone tools, is 2.6–2.5 million years at Gona in Ethiopia. These stone tools are attributed to the Oldowan stone tool industry (named after Olduvai Gorge in Tanzania, where they were first found).

The Oldowan is a very simple stone tool industry consisting of cobbles that have had small flakes removed from them to make a type of tool known as choppers. Both the flakes themselves and the choppers were then used as tools, but what were the tools used for?

Andy Herries is Senior Research Fellow at the University of NSW School of Medical Sciences. He helped estimate the age of the archaeological remains at FwJj20.

Fool’s Gold: The Search for Early Life

Michaela Partridge examining a banded iron formation from the Archean.

Michaela Partridge in the Pilbara examining a banded iron formation from the Archean.

By Michaela Partridge

The golden mineral, pyrite, is a valuable tool in the search for the secrets of early life on Earth.

Imagine a planet where the atmosphere is a hazy methane greenhouse and the surface is barely warmed by a faint young star that is only two-thirds as bright as the Sun we know today. An alien world with anoxic oceans full of microscopic life forms, most of which would perish in the oxygen-rich atmosphere that we depend on for our survival.

Michaela Partridge is completing her PhD in astrobiology at the University of Queensland.

Cosmic Time Machine

Moon craters

Craters reveal the Moon's turbulent history.

By Marc Norman and Tim Wetherell

Precise dating of impacts on the Moon might contribute to a better understanding of life on Earth.

The planets of our solar system formed about 4.5 billion years ago from a collapsing disk of dust and gas rotating around the axis of an infant star. Within this cosmic colosseum, violent events of enormous magnitude played out. The early Sun flared hot magnetic jets deep into outer space; supersonic shock waves swept across the disk; and portions of the disk were heated to temperatures in excess of 1500°C.

Marc Norman is a Senior Fellow with the Research School of Earth Sciences at the Australian National University, where Tim Wetherell is Science Editor.

How to Make a MegaStar

Big Bang

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By Peter Barnes

Astronomers are still largely in the dark when it comes to understanding how the most massive stars form, but they are now pursuing several new strategies to solve this enduring mystery.

Galaxies are the building blocks of the universe. To understand how galaxies have evolved over cosmic time, you have to understand their overall ecology; that is, the global process of star birth from interstellar gas and dust, through stellar evolution and on to stellar death, when material enriched in heavy elements is returned to the interstellar medium and begins the cycle anew.

Peter Barnes is an Assistant Scientist in the Astronomy Department at the University of Florida.

Big Bang Conundrum

By Stephen Luntz

An unexpected consistency in the concentration of deuterium atoms in the distant universe might be a curious coincidence, or it could rewrite our understanding of the Big Bang.

Deuterium atoms, which combine a neutron with the proton and electron of an ordinary hydrogen atom, were formed during the Big Bang. To the best of our knowledge no natural processes since then have created any more, while on the other hand deuterium is sometimes destroyed within stars.

Cosmologists are interested in finding out how much deuterium was initially created in the Big Bang. In the youngest galaxies we can observe it at about 30 parts per million hydrogen atoms.

Thank God for the New Atheists

Richard Dawkins

Richard Dawkins is one of the New Atheists who are fulfilling the traditional role of prophets. Getty Images

By Reverend Michael Dowd

Religious people of all backgrounds and orientations need to heed what atheists such as Richard Dawkins are saying if they want their traditions to remain relevant to modern society.

Since April 2002, my wife and I have lived entirely on the road. We’ve addressed more than 1000 groups across North America, teaching and preaching the epic of evolution as our common creation story. Last year, on the day I learned I had cancer, I pondered:“If I have only one message left to communicate, what would it be?” The answer was: “Show Christians how the New Atheists are God’s prophets”. One year later, with cancer in remission, this is still my core message.

Rev. Michael Dowd is the author of Thank God for Evolution: How the Marriage of Science and Religion Will Transform Your Life and Our World (2009, Plume). See http://ThankGodforEvolution.com

Turning Water into Fuel

Environmental footprint

A major challenge facing the world is to develop sustainable, non-carbon-based sources of energy. One of the most obvious, renewable and non-carbon-based sources of energy is sunlight.

By Zhiguo Yi and Ray Withers

A simple inorganic semiconductor could deliver an artificial photosynthesis process that will convert sunlight and water directly into hydrogen and oxygen, thus providing the renewable fuel of the future.

Modern society depends on a continuous, reliable supply of energy that must be available both day and night. At the moment, the burning of carbon-based fossil fuels such as coal and oil provide the overwhelming majority of the world’s current, and projected, energy needs.

The problem rushing headlong towards us is that fossil fuels are non-renewable, and the burning of them leads to ever-increasing levels of pollution as well as a systematic increase in the level of greenhouse gases such as carbon dioxide (CO2) in our atmosphere. This, in turn, leads to human-induced climate change.

Zhiguo Yi is a Postdoctoral fellow and Ray Withers is Professor of Materials Chemistry at the Research School of Chemistry, Australian National University. The assistance of Tim Wetherell in the writing of this article is acknowledged.

Dangerous Ground

Tim Inglis searching for B. pseudomallei in the Kimberley.

Tim Inglis searching for B. pseudomallei in the Kimberley.

By Tim Inglis

A deadly bacterium lies dormant in tropical soils until it is disturbed by natural disasters, mining operations or even gardening.

Outbreaks of serious infectious diseases were predicted after the first wave of floods in Pakistan. Weeks later those predictions were proved sadly accurate as the human tragedy unfolded, with further flooding adding to the human misery caused by cholera, malaria, dengue and skin infections.

Tim Inglis is a medical microbiologist with PathWest Laboratory Medicine WA, QEII Medical Centre, Perth.

New Tactics in the War on Weeds

The native herb Lomandra stands in front of the invasive weed African lovegrass

The native herb Lomandra stands alone in front of the invasive weed African lovegrass, which was introduced into Australia for pasture improvement but was found to be unpalatable to grazing livestock and native animals.

By Jennifer Firn

Sometimes fertilisers can be more effective than herbicides when it comes to controlling weeds.

Invasive weeds are one of the most serious threats to the unique and rich biodiversity of Australian rangelands. Many Australians may not know much about rangelands, as only two million people live in this region, but they cover more than 70% of the land mass – more than 6 million km2 – and are packed full of unique and highly valued plants and animals, including 53 of Australia’s 85 biogeographical regions and five of 15 identified biodiversity hotspots.

Dr Jennifer Firn is OCE Postdoctoral Fellow at CSIRO Ecosystem Sciences.