Caption: Monarch butterfly egg (Danaus plexippus) on a milkweed leaf. In two to five weeks of egg-laying a female will lay about 700 eggs. Generally, eggs hatch in 4 days, but cool temperatures delay hatching up to 12 days. Newly hatched caterpillars feed on milkweed, their sole source of food. Milkweed contains a poison that is harmless to monarchs, but which sickens predators. Birds and other predators soon learn to avoid the bright colors of monarch caterpillars and adults. A caterpillar eventually attaches itself to a twig, sheds and forms a chrysalis from which an adult monarch butterfly emerges. An adult lives six weeks in summer but those that migrate can live six to nine months over winter.
Magnification*: x10
Type: SEM
Copyright 2006 Dennis Kunkel Microscopy, Inc.
Keywords: 04.01.06,butterfly egg,butterfly egg case,Danaus plexippus,insect,insects,invertebrate,invertebrates,monarch butterfly,monarch egg,SEM,20070F