Iron replaced bronze as the prime material for tool and weapon production during the transition from the Bronze Age to the Iron Age. The replacement was gradual — at different times in different regions. There were things made of iron in the Bronze Age, but the iron was different. During the formation of a celestial body like Earth, nearly all nickel drifts towards the molten iron core and becomes extremely rare on the surface. Some meteorites, however, are caused by the shattering of Earth-like bodies. If these meteorites are composed of core material, they mostly contain iron with high levels of nickel and cobalt. Meteoric iron is already in a metal state, ready for use, and geochemist Albert Jambon determined that all Bronze Age artefacts were made of meteoric iron! The iron in terrestrial ores must first undergo the process of reduction to finally yield the intended metal. This is smelting — the breakthrough that marked the beginning of the Iron Age. With smelting, Iron Age cultures could afford to forgo the rare extraterrestrial iron and tap into the abundant terrestrial iron ores.

SNEAK PEEK

1. Game of clones

Our bodies are the set of ‘Game of Clones’ — a continuous battle for space between normal and mutant cells. Low doses of radiation, similar to three CT scans’ worth, are regarded as safe. Who discovered that even these small doses can promote cancer-capable cells?

1. Dr David Fernandez-Antoran (Wellcome Sanger Institute)

2. Carrying babies

About 64% of all men and 73% of all women hold a baby with their left arm. Emotions are primarily processed in the brain’s right hemisphere. People tend to move their baby into their left visual field, which is linked to the brain’s right hemisphere. Who explained this?

2. Julian Packheiser (Ruhr-University Bochum)

3. Workout in space

Several astronauts have fainted when they came down to Earth. The longer the time spent in a gravity-free environment, the greater the risk appeared. Who showed that this won’t happen if people perform the individualized exercise for two hours a day during space flight?

3. Dr Benjamin Levine (UT Southwestern Medical Center)

4. It’s buying time

When you hire someone to do a chore, you are not just being lazy; you buy time. And buying time has similar benefits for happiness as having more money. These benefits aren’t just for wealthy people. Who documented the same outcome across the entire income spectrum?

4. UBC psychologist Elizabeth Dunn

5. Needle on the skin

A tattoo needle punctures the skin’s uppermost layer and releases the pigments into the layer below. If you fix chemical sensors at spots in the body, they can record changes inside for a very long period of time. Who conceived tattooing as a tool for diagnosis in this manner?

5. Ali K. Yetisen (Technical University of Munich)

6. Reading with kids

Parents are in line for non-academic benefits if they follow the routine of reading with their children every day. Mothers who frequently do this have fewer disruptive behaviours from their children, which indicate no or little harsh parenting behaviours. Who studied the effect?

6. Manuel Jimenez (Robert Wood Johnson Medical School)

7. Why 200 million!

Why does it take 200 million sperms to fertilize a single egg? Very few sperms survive the bombardment by the female immune system. Who proposed the evolutionary view that, for an egg, “being too easy to fertilize is bad; being too difficult to fertilize is also bad”?

7. Molecular anthropologist Pascal Gagneux”

8. No math gene!

There is no math gene! Only practice matters. This may raise a few eyebrows, but it is important to practice every single kind of math subject (algebra, geometry and so) to be good at all of them. Who demonstrated that these skills are not something you are born with?

8. NTNU psychologist Hermundur Sigmundsson

9. Vocal learners

Chickadees identify high arousal in other chickadees, humans and giant pandas. If humans and songbirds have an innate ability to understand the vocalizations of other species, would other vocal learners have this same propensity? Which PhD student posed the question?

9. Jenna Congdon (University of Alberta)

QUIZ No. 913

1. Last chance tourists put a site’s “destination status” in danger. Who argued so?

– Patricia Hill Collins
– Annah Piggott-McKellar
– Randall Collins

1. Annah Piggott-McKellar

2. In fear, our eyes open wider. In disgust, our eyes narrow. Who analysed the trait?

– Adam Anderson
– Dr Lillian Eva Quan Dyck
– Walter Rudolf Hess

2. Adam Anderson

3. Ask girls to “do science”, not to “be scientists”. Who suggested this alternative?

– Elisabeth Badinter
– Richard Fritz Behrendt
– Marjorie Rhodes

3. Marjorie Rhodes

4. Who killed himself upon hearing of the Nazi plan to create the Warsaw Ghetto?

– Henry George Liddell
– Marcas Mac Coinnigh
– Samuel Adalberg

4. Samuel Adalberg

5. Which Indian-born foreigner is known as the father of scientific forestry in India?

– Dr Hugh Cleghorn
– Lawrence Samuel Durrell
– Rudyard Kipling

5. Dr Hugh Cleghorn