
On gravitational pull and buoyancy : "Janthina janthina, the descendant of the first snails that got lost in space, ... build themselves a large bubble raft, often bigger than themselves, to ensure that their total density is always less than the seawater they're in. So they always float, upside down (bubble raft up, shell beneath), preying on passing jellyfish. "
More science learning for #booked2021 and photo from Google.