Q1: Why do some birds lay brightly colored blue eggs if predators target them?
A1: Blue and green coloration, created by biliverdin, protects the developing embryo from solar radiation damage in open, sunny nests. The pigment also provides optical camouflage in shaded forest canopies, where shifting dappled light breaks up the egg's solid outline.
Q2: How does the new Ethiopian snake crack shells without normal teeth?
A2: The snake swallows the egg intact using loose, highly stretchable jaw ligaments. Once the egg reaches the esophagus, modified downward-pointing projections on the cervical vertebrae press into the shell, cracking it under muscular pressure before the snake spits the crushed shell back out.
Q3: How do scientists extract ancient DNA from broken fossil shells?
A3: The calcite matrix of an eggshell traps and seals proteins and genetic material within microscopic crystal boundaries. By dissolving the mineral layers under cold chemical conditions, geneticists isolate intact ancient eggshell DNA that degraded far less than DNA in porous bone.
