Migration and Breeding

The relatively cool and rainy weather in the Leviathan has lead to a record number of butterflies gathering in Lebanon. Resting there on their way from Africa to Europe, the migrant insects amazed people living in Lebanon where the population of butterflies spilled out of the natural areas and into farms and villages due to its size. That country has not seen such a large swarm since 1917. Because of annual spurt of plant growth this time of year, both Israel and Lebanon are resting spots for migratory species that fly between Africa and Europe seasonally.

North America has its own migratory species, including the monarch butterfly. The life cycle of the monarch butterfly has several stages and is linked to a multi-generational migration route. During the warm months, monarch butterflies in the USA develop from eggs to larvae to pupae to mature breeding butterflies in 2 to 5 weeks before they die. After a few generations of living like this, the last generation for the year pauses its development before reaching the breeding stage and migrates to Mexico or California.

The timing of migrations and breeding seasons matches the seasonal prevalence of food and competing species. Migratory birds evolved from species that stayed in the same location year round. Their ancestors gradually adopted a new breading ground or wintering ground. Over many generations they kept moving this secondary home farther and farther from the ancestral home until migration routes evolved to be thousands of kilometers long.

Every land on Earth has a unique climate that local populations adapt to so that they are in harmony with the seasonal rhythms. There are ideal times for certain activities, and those times depend on the location. Migratory populations evolved to be in harmony with the seasonal variations in more than one location. Creatures of flesh and blood will never be able to change the seasons, but migration makes it possible for them to select from the many different seasons that exist on Earth at any given time.

After earning a Masters of Science in Ecology and Evolution, Joseph Dunsay became a science writer for international audiences. His LGBT erotic e-book launched in the summer of 2015.