Nature

What were the first animals? The fierce sponge–jelly battle that just won’t end

For almost two decades, scientists have debated whether sponges or comb jellies are the first animal lineage. Now some are ...

Silicon Valley Wants to Build A.I. That Can Improve A.I. on Its Own

Ricursive Intelligence, founded by two former Google researchers and valued at $4 billion, is among several efforts to ...