NATS 1550 Final: Animal Migration Final Exam Review (Case Studies)
Document Summary
Cannot survive harsh winter: solution annual migration south in early autumn. Unusual because: southbound adults survive entire winter for return trip. Intergenerational relay: each breeding season, up to 5 generations of butterfly live, reproduce and die in north america. Adults before/ in late summer, have no sex organs. End of august: obese , ready to head south. Stop-start migration stop for flowers (fat reserves) Stop at california to sleep in pines for winter (5 million of them) Or mexico s volcanic mountain belt (eastern monarchs) (100 million) Which sleeping, they don t get eaten they lace their body with toxins. Get the toxins from their main food source, milk weed plants. During days, they mate; then head north to lay their eggs; then they die. Adults of this generation = 9 months old (oldest of the butterflies) Later generations more northward, reoccupying breeding grounds. Egg larva (caterpillar) pupa (chrysalis) butterfly (up to 5 generations per year)