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The era of greyhound racing in the U. See how people have imagined life on Mars through history. And even the plants converge. This Lantana , which is likely native to Mexico, but weedy and invasive elsewhere, is frequently confused with tropical milkweed. Alas, monarchs are disinterested. A bit unusual in that I typically see eggs on the undersides of leaves on this plant species. It was late February and time to see the monarchs at their overwintering sites before they journey north.
Due to storms in the past couple of years, the forests on the way, walking to the butterfly colonies, were very bright and open. Fallen trees had been removed for timber and the under-story was uncharacteristically blooming with many flowers.
This image is from a walk up to the top of Cerro Pelon. Atop Cerro Pelon… but the altitude was too much for me. We started at ft and went up to to the peak in 3 hours…. Monarch mating is best described as coercive, but this has generated some controversy in the scientific community see Chapter 4 of my book. Some mating occurs at the end of the overwintering season beginning late February as seen here. The male with black spots showing on the hind wing is nearly completely attacked to the female back-to-back ….
A pile of dead monarchs… compiled on my way down the mountain, heading back to Morelia. An evening keynote lecture that focused on the knowns and unknowns of the monarch decline and possible means for conservation. Ealier this week, the overwintering numbers from were announced by WWF Mexico. As always, I had my ears peeled for milkweeds and monarchs. This is Plumaria , sometimes called frangipani, a group of a dozen or more species native to Mexico and further south.
These shrubs and small trees in the milkweed family Apocynaceae have familiar seed pods, with a twin pair shown above.
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How long can people live? Make a Handheld Gimbal out of your Phantom 3 Drone. How the Body Adjusts to Altitude. Collecting Bugs in Sweden. Collecting Bugs in the Amazon. Second, they do not reproduce right after they emerge. In response to decreasing temperatures and shortening daylengths at the end of the summer, their reproductive organs remain in an immature state.
Instead of mating and laying eggs, they spend their time drinking nectar and clustering together in nighttime roosts in preparation for their long journey south. This delayed maturity is called diapause.
Most of the monarchs will remain in this condition until the following spring, when they begin to mate in the overwintering colonies. During September, October, and early November, migratory adults fly to overwintering sites in central Mexico, where they remain from November to March.
In March, they begin to journey north, laying the eggs that will become the new Generation 1 along the way. Annual Life Cycle. Generation 1 Monarchs in Generation 1 are the offspring of the monarchs that overwinter. Life Cycle Summary The first monarch generation of the year begins when females that have spent the winter in Mexico lay eggs in northern Mexico and the southern U. Generation 2 Monarchs in Generation 2 are the grandchildren of the overwintering monarchs.
Life Cycle Summary Generation 2 larvae are widely distributed throughout the eastern United States, first beginning to appear in the south in early May, and in the north in mid to late May. Life Cycle Summary Generations 3 and 4 monarch eggs are laid throughout the northern part of their range in July and August.
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