Â鶹´«Ã½

Last Word

D73X1R An colorful adult midnight snapper swims over the reef

How do fish recognise others of their own species?

Some expert weigh in on this issue, which turns out to be much more complicated than it looks

Regulars
Two scientists use a massive, illuminated periodic table of elements as they discuss the element holmium in the Lawrence Hall of Science at the University of California, Berkeley. (Photo by ?? Ted Streshinsky/CORBIS/Corbis via Getty Images)

How many known elements could we delete without ill effect? Part 2

Regulars
H99WWH Low Angled portrait of a German Shorthaired Pointer dog.

This week’s new questions

Regulars

What sized planet would make space travel impossible due to gravity?

Regulars
W447EF hand is holding ice cream cone in front of a beach in Brittany, France

Why is ice cream so delicious?

Regulars
A 3D illustration of the now debunked competing conspiracy theory that the Earth is flat, as it appears from land, rather than spherical. Earth texture maps courtesy of NASA.gov; Shutterstock ID 1240127368; purchase_order: -; job: -; client: -; other:

What would the horizon look like on a disc-shaped planet? Part 4

Regulars
two bumblebees on a yellow flower collects pollen, selective focus, nature background; Shutterstock ID 705344482; purchase_order: -; job: -; client: -; other:

This week’s new questions

Regulars
Two Astronauts on the Alien Planet Discover Plant Life. Space Travel, Discovery Of Habitable Worlds and Colonization Concept.; Shutterstock ID 1042736296; purchase_order: -; job: -; client: -; other:

Are there plants that could survive as a food source on the moon?

Regulars
PF9N2P Honeybee stick on a window

Are flies following a strategy when they keep hitting into a window?

Regulars
2BXTXNE Red giant star. Sun. Earth landscape. Moon. Venus. Solar system

When the sun engulfs Earth, will the remnants form new planets? Part 2

A reader (and astronomy expert) gets to grips with this one, pointing out that Earth’s future fate is still uncertain – and that elements found in nuclear waste aren't great building blocks for biological life

Regulars

What’s the optimal ratio of frozen peas to cold tap water? Part 4

Regulars

This week’s new questions

Regulars

If everyone got rid of their mobile phones, what would happen?

Regulars

Why do some of us enjoy exercising and others don’t?

Regulars