A science presenter, writer, speaker & former TV host; author of The Skeptic's Handbook (over 200,000 copies distributed & available in 15 languages).


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Ebola — time for action

I trained in microbiology so I’ve watched the Ebola situation unfold with quiet dread.  When my favourite lecturer was asked what was worst of the worst infectious epidemics he could imagine, he responded that the sum of all fears would be a cross between Ebola and Newcastle’s disease. It would be a highly fatal hemorrhagic disease, combined with a highly contagious virus spread by birds. It’s time to talk of the dark dark possibility that one mutation could bring — the aerosolization of Ebola.

As long as this Filovirus stays in its current form, spread only through direct contact with an infected and obviously ill person, we have a chance to limit the spread. Quarantine is effective. If it goes airborne, the task becomes like preventing the flu, but without clinically tested vaccines, in a totally unprotected population, and with a 60% fatality rate. This is the nuclear option.

The Ebola virus has several different forms, and at least in animal studies, it has “gone airborne” before. Theoretically, it’s an odds game. The more times the virus is copied — the better the odds are that the right mutation will occur. To be brutally blunt, every infected person is another [...]

Could early antibiotic use lead to lifelong weight gain?

For a weekend curiosity: this study caught my eye.

What if part of the modern obesity epidemic was due to antibiotic use? It may be that if we feed babies antibiotics during a certain window of development, their metabolism changes in ways that last for life (say hello to Syndrome X — sigh). For years, evidence has been gathering that the bacteria in our gut have major contracts and complicated deals going with our immune system. Now this study in lab mice suggests serious negotiations might be going on between bacteria and our developing metabolism too.

The quote of the day: “When we put mice on a high-calorie diet, they got fat. When we put mice on antibiotics, they got fat,” explains Dr. Blaser. “But when we put them on both antibiotics and a high-fat diet, they got very, very fat.”

The study showed that it was not the antibiotics per se that caused the change, but the microflora. Perhaps immediately restocking with the right bacteria might negate the side-effects of the antibiotics.

Our intestines have one to two kilograms of little critter inhabitants, so it is quite the ecosystem inside there. This study tantalizingly suggests we may yet [...]

Most of Earth covered with life powered on hydrogen. Living Rocks?

File this under: What don’t we know?

We just discovered slice “2″ is alive.  |1 – Continental crust | 2 -Oceanic crust | 3 – Upper Mantle | 4 – Lower Mantle | 5 – Outer Core | 6 – Inner Core | Image Credit: Dake

You might have thought that photosynthetic life forms had the Earth covered, but according to some researchers the largest ecosystem on Earth was just discovered and announced last Thursday, and it’s powered by hydrogen, not photosynthesis.

The Oceanic Crust is the rocky hard part under the mud that lies under the ocean. It covers 60% of the planet and it’s 10km thick. (The oceans themselves are a paltry 4km deep on average.) We’ve known for years that the isolated hot springs in trenches held life. But who thought that all the hundreds of thousands of square kilometers of basalt rock in between had its own life cycle? Last week a group from the Center for Geomicrobiology at Aarhus University, Denmark announced that they had drilled through crust that was 2.5km underwater and 55 km away from anything that mattered. They found life in the basalt.

“We’re providing the first direct evidence of life [...]

Cloud forming bacteria?

File this under: “How little we know.”

The upper troposphere is apparently teeming with particles of bacteria and fungi, surprising researchers.* Proving that life is tenacious and that microbes can survive just about anywhere, a team at Georgia Institute of Technology have discovered that quite a bit of what we assumed was dust and sea-salt may be bacteria aloft. Some of the little critters made it as high as the upper troposphere which is 10km up (where commercial flights cruise). No one is quite sure if the microbes “live” up there, or were just visiting.

The study showed that viable bacterial cells represented, on average, around 20 percent of the total particles detected in the size range of 0.25 to 1 microns in diameter. By at least one order of magnitude, bacteria outnumbered fungi in the samples, and the researchers detected 17 different bacteria taxa – including some that are capable of metabolizing the carbon compounds that are ubiquitous in the atmosphere – such as oxalic acid.

The bacteria were probably tossed up there by wind and waves:

When the air masses studied originated over the ocean, the sampling found mostly marine bacteria. Air masses that originated over land had [...]

Toxoplasmosis: could that latent infection affect people’s behavior?

This is disturbing news. What if eating undercooked meat, gardening, or having a cat could give you an infection which stayed with you for life, nested in cysts in your brain? Worse, those cysts somehow affected your personality, possibly putting you at increased risk of suicide, schizophrenia, or car accident? And here’s the stop-you-in-your-tracks point: up to one third of humanity may harbor this protozoan. That is one very successful parasite.

Infection rates are frighteningly high: as much as 10-20% of the population in the US, 30-40% of Czechs, and 55% in France.

Sounds like a plot for a bad sci-fi but we know that Toxoplasma gondii makes small mammals take life threatening risks – an infected rat finds cat-urine “attractive” and runs about more, being fearless, but getting eaten: good for the parasite, not so good for the rat. Our brains may be  larger but they are made with much the same building blocks and tools.  Rabies is known to stir larger mammals into a rage, and there are “a truckload” of examples from the insect and fish world of parasitic mind control. Hmmm.

Toxoplasmosis is thought to be a nasty parasite that affects pregnant women and immune-compromised people, [...]

Could Green BioGas ferment botulism?

Clostridium Botulinum is one of the toughest bugs around. And its toxin (a neurotoxin) is also one of the most deadly, yet strangely popular at the same time. Yes botulinum toxin is also known as BoTox and tiny quantities paralyze nerves. Small quantities can be fatal as nerve damage progresses to respiratory failure.

In it’s spore stage you can boil the bug to no avail — it’s one of the reasons boiling isn’t enough for tins, or sterilization of lab equipment. To kill these spores you need 121C in an autoclave (or pressure cooker). The toxin itself can be destroyed at 100C.

A million acres of land are producing corn for biogas plants in Germany.

German “Green” Biogas Plants Producing Deadly Botulism – “Could Be Catastrophic To Wildlife”

By P Gosselin on 19. Mai 2011 No tricks Zone

German sporting and dog magazine Wild und Hund reports that thousands of domestic and wild animals are falling ill from tainted waste from green “climate-friendly” biogas plants, which is then used as an agricultural fertilizer in fields.