Spear and telescope: what they have in common

1. Step 1. Spear — evolved into — Harpoon. A spear with barbs.
2. Step 2. Harpoon — is made of — Bone. The oldest harpoons (Katanda, ~90,000 years ago) are carved from bone.
3. Step 3. Bone — is material for — Spectacle frame. The first frames were made of bone and horn.
4. Step 4. Spectacle frame — is part of — Glasses. A frame.
5. Step 5. Glasses — evolved into — Telescope. The first telescopes were assembled by spectacle makers.

Open Evothings