WHY WE LOVE 戀之火 Dr. Angela Ng Wing Ying MB, BS, DFM, MRCGP • Our ancestors lived in the forests of east Africa about 8 million years ago. • Later they descended from the forest canopy to build a new world on perilous ground. • 3.5 million years ago, our ancestors were walking erect on two legs. • Hands developed for gesturing, and mouths were freed for words. • Females carried their babies in their arms instead of on their backs. • They needed mates to help feed and protect them while they nursed a child. • Pair-bonding with a mate evolved. • 1.8 million years ago, our ancestors (Homo erectus) began to speak. • Probably animal attraction developed into a human form of romantic love around this time. • They harnessed fire. Cooking food helped digestion and destroyed microorganisms & toxins. • The Homo erectus’ brain evolved into a bigger and more powerful brain • Big-headed infants could not pass through the small human pelvis. • Therefore infants were born much earlier, when they were still helpless and undeveloped. • The job of parenting became long and overwhelming. • Courtship intensified. Individuals needed to choose a compatible long-term partner. • The brain circuitry for human romantic love evolved. • Living things live, reproduce and pass their DNA to future generations.