Monarch Butterfly Development

Daily photos of every stage of development from egg to adult, including caterpillar and chrysalis. There is also a chart with a quantitative analysis of caterpillar growth. Please see the About page for more information and commentary.
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Day 1: July 23, 2020 4:23 PM This photo was taken about 5.5 hours after a female monarch butterfly visited milkweed plants in my yard and presumably laid this egg, which was the only one I...
Day 1: July 23, 2020 4:23 PM
This photo was taken about 5.5 hours after a female monarch butterfly visited milkweed plants in my yard and presumably laid this egg, which was the only one I…
Day 2: July 24, 2020 9:35 AM There is no obvious change from the previous day.
Day 2: July 24, 2020 9:35 AM
There is no obvious change from the previous day.
Day 3: July 25, 2020 8:56 AM There is no obvious change from the previous day.
Day 3: July 25, 2020 8:56 AM
There is no obvious change from the previous day.
Day 4: July 26, 2020 9:56 AM The egg is starting to hatch.
Day 4: July 26, 2020 9:56 AM
The egg is starting to hatch.
Day 4: July 26, 2020 4:04 PM About 6 hours after hatching began, a tiny caterpillar has emerged. There is no sign of the egg shell, which was probably eaten by the caterpillar. At this...
Day 4: July 26, 2020 4:04 PM
About 6 hours after hatching began, a tiny caterpillar has emerged. There is no sign of the egg shell, which was probably eaten by the caterpillar. At this…
Day 5: July 27, 2020 9:30 AM The caterpillar has already grown considerably and is starting to show the colored bands typical of monarch butterfly caterpillars. Length=3.57 mm. Width=0.76...
Day 5: July 27, 2020 9:30 AM
The caterpillar has already grown considerably and is starting to show the colored bands typical of monarch butterfly caterpillars. Length=3.57 mm. Width=0.76…
Day 6: July 28, 2020 10:00 AM Length=5.56 mm. Width=1.18 mm. Volume=6.06 cubic mm.
Day 6: July 28, 2020 10:00 AM
Length=5.56 mm. Width=1.18 mm. Volume=6.06 cubic mm.
Day 7: July 29, 2020 9:27 AM Length=6.60 mm. Width=1.29 mm. Volume=8.61 cubic mm.
Day 7: July 29, 2020 9:27 AM
Length=6.60 mm. Width=1.29 mm. Volume=8.61 cubic mm.
Day 8: July 30, 2020 8:43 AM Length=9.01 mm. Width=2.17 mm. Volume=33.3 cubic mm.
Day 8: July 30, 2020 8:43 AM
Length=9.01 mm. Width=2.17 mm. Volume=33.3 cubic mm.
Day 9: July 31, 2020 8:24 AM Length=8.29 mm. Width=1.82 mm. Volume=21.5 cubic mm.
Day 9: July 31, 2020 8:24 AM
Length=8.29 mm. Width=1.82 mm. Volume=21.5 cubic mm.