Photographic memory is the ability to recall a past scene in detail with great accuracy – just like a photo. Although many people claim they have it, we still don’t have proof that photographic memory actually exists. However, there is a condition called Highly Superior Autobiographical Memory (HSAM) that allows people to recall past events in detail, along with the exact dates when they occurred. For example, they may be able to tell you what they ate for lunch on 1 May 1999 and what day of the week it was (Saturday). But HSAM has been identified in fewer than 100 people worldwide, and while their memories are exceptional, they still aren’t as reliable as photographs.
The East Antarctic plateau is the coldest place on Earth
The coldest temperature ever recorded was a frosty -94°C, taken at the East Antarctic plateau, a region that stretches for more than 1000 kilometres. This measurement means the plateau is the coldest place on Earth – not that anyone was actually there to record such a temperature, though. The reading was collected using data from satellites across Dome Argus and Dome Fuji, two ice domes that sit at thousands of metres above sea level. Results suggested the air temperature could be around -94°C, but researchers think that the dry air around the area could cause temperatures to get even colder.
Queen bees can lay more than 1500 eggs in a day
Queen honeybees live for up to seven years and can more than 1500 eggs a day, which equates to more than their body weight. Rather than working, like the vast majority of colony members, queens spend their lives devoted to laying eggs while other bees serve them. Instead of pollen and honey, the queen is fed royal jelly, which workers secrete from glands in their heads. When a queen grows old, a colony will select a new one, but in some colonies there may be multiple new queens, who have to fight each other to the death. The survivor will fly to a drone congregation area and mate with around a dozen drones, storing up to 6 million sperm in her body.
Laughing gas may have ended the last glacial period
Laughing gas, otherwise known as nitrous oxide, has been used as an anaesthetic since the 19th century. These days, it is most commonly found in small, steel cartridges sold to the catering industry for making whipped cream. However, nitrous oxide is also a potent greenhouse gas and ozone-depleting chemical. Although it is present in the atmosphere at much lower concentrations than carbon dioxide – just 330 parts per billion – it has 300 times the heat-trapping capability. Indeed, a pulse of nitrous oxide released from plants 14,500 years ago may have hastened the end of the last glaciation.
We don’t necessarily yawn because we are tired
We tend to think of yawning as a sign of being tired or bored. That probably explains the popular perception that it is a way to get more oxygen into the blood to increase alertness. However, psychologist Robert Provine at the University of Maryland tested this idea and found people were just as likely to yawn when breathing air high in oxygen. A closer look at when people yawn suggests another explanation. It turns out that most spontaneous yawning actually happens when we are limbering up for activity such as a workout, performance or exam, or simply when we wake up. That has led to the idea that yawning helps us gear up by increasing blood flow to the brain.
The placebo effect can depend on whether a pill is colourful
The placebo effect is the mysterious reduction in a patient’s medical symptoms via the power of suggestion or expectation, the cause of which remains unexplained. However, what we do know is that a number of different factors can affect the power of the placebo effect. It can be triggered by administering pills, injections or surgery, or even just an authority figure assuring a patient that a treatment will be effective. In fact, experiments have shown that the power of the placebo effect depends on surprising factors like the appearance of tablets. For example, colourful pills work better as a placebo than white ones.
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