natural
天 · 4 strokes
Depicts a person (大) with an emphasized head. Based on the original meaning "head". The meaning later shifted to "top", "high", and "sky".
然 · 12 strokes
Phonosemantic compound. 灬 represents the meaning and 肰 represents the sound. Based on the original meaning "burn", now written as 燃. The current meaning is a phonetic loan.