Here are the week’s #weirdscifacts from Twitter!  This marks the 500th weird fact I’ve done, as well!

494. July 20: A migration strategy for some snails: get eaten by birds? How did snails manage to spread across so many islands separated by vast seas?  It turns out that a surprising number can survive a passage through a bird’s digestive tract, suggesting they were eaten and pooped out at a new destination! (by @theatavism)

495. July 21: May earthquakes in Maine due to ground relaxing from weight of ice during last Ice Age!  During the Ice Age, massive sheets of ice a mile high stretched across Maine.  This compressed the ground, and since the ice has receded the ground has been expanding out, giving little tremors.

496. July 22: Sometimes, injured muscles grow back as … bones.  The origin of this odd complication to injury is only now being determined.  (h/t @erikmal)

497. July 23: Fishing spiders — hunt fish while walking on water!  I always find it particularly ghastly when arachnids or insects prey on “higher” animals.  (h/t @timrs2001)

498. July 24: Scientist Robert Cornish, who in 1934 worked on “raising the dead” — namely, dogs. A Time Magazine article written about the experiments at the time can be read here.  A “see saw” was used to circulate blood in the victims to be resurrected.

499. July 25: Coronal mass ejections from the sun can eject 220 billion lbs of material at 2 million mph! That is a *lot* of material!  Many of these ejections can happen every year.

500. July 26: The stone-age Tasaday tribe, “discovered” in 1971 — a complete hoax, authentic, or in between? The original 1971 Time Magazine article can be read online.