51动漫

close up the fly on the window, on the glass, the concept of sanitation, dangerous insects, insect repellent, copy space; Shutterstock ID 1168097506; purchase_order: -; job: -; client: -; other: -

Why can a fly enter my home easily, but not escape as easily? Part 2

There is no need to invoke Maxwell鈥檚 demon here, says one reader, while another points out that flies evolved long before humans invented glass

explosion of atomic bomb on background of sky; Shutterstock ID 51881707; purchase_order: -; job: -; client: -; other: -

This week鈥檚 new questions

Back view of 9 year old girl hiking, walking alone in the forest by the river with a backpack in early spring. Beautiful idyllic nature.; Shutterstock ID 2302035971; purchase_order: -; job: -; client: -; other: -

At what age would a human child be capable of surviving in the wild?

Man opening door of retro refrigerator freezer.; Shutterstock ID 2275541755; purchase_order: -; job: -; client: -; other: -

Is it more efficient to leave the fridge open if pouring milk for tea?

2G4X8CE Female runner running with dogs in canicross style on hill

Does having four legs aid dogs with climbing? Part 2

F6YK0A Weltzeituhr on Alexanderplatz in Berlin

This week鈥檚 new questions

Fox with fresh fish standing on a stone in a lake. Amazing capture of this predator. Nature and wildlife is so rewarding and people still have a lot to learn from all of this.; Shutterstock ID 1041384616; purchase_order: -; job: -; client: -; other: -

Why don鈥檛 animals other than humans get sick from uncooked food?

Reindeers migrate for a best grazing in the tundra nearby of polar circle in a cold winter day.; Shutterstock ID 605430995; purchase_order: -; job: -; client: -; other: -

Has Earth鈥檚 shifting north magnetic pole affected migrating animals?

2G8TR2M Young woman sitting and holding a blue mug of tea outdoor

This week鈥檚 new questions

2HMRRGF Madrid, Spain - March 6th, 2021: Isidore of Seville statue at National Library of Spain, Madrid. Medieval Spanish scholar

Once life is established, is the evolution of intelligence inevitable?

Our readers clash over this difficult question, given that only one example, under one set of conditions, is currently known to us

Why aren鈥檛 humans covered in hair like other primates are? Part 2

This week鈥檚 new questions

Is there a maximum possible acceleration?

Does having four legs aid dogs with climbing?