SPECIES YET SO NEAR, YET SO FAR

DURING the early stages of Earth's evolution, when the supercontinent Pangea split into two parts — Laurasia and Gondwanaland — which further moved apart, creating the world geography we know today, there was a drastic shift in the evolution of life as well.

- HRITHIK KIRAN BAGADE

An evident result was the variety and diversity in the animal kingdom, divided by geography, but bound by Earth's ever-changing nature.

One of the most intriguing instances of this phenomenon rests in biogeographical boundaries.

A biogeographical boundary refers to the geographic areas or regions that delineate the distribution of different species, ecosystems, or biological communities.

These boundaries are shaped by a combination of environmental factors, such as climate, geography, and ecological processes, as well as historical events like the Continental Drift, glaciations, and migration patterns.

They also explain the causes for biodiversity, species adaptation, and the interplay between organisms and their habitats across different regions of the globe.

One of the most interesting biogeographical boundaries which particularly depicts how species on either side have developed remarkable features over time, is the Wallace Line that separates the flora and fauna of the islands of Asia from those of Australia.

Named after British naturalist Alfred Russel Wallace, who first identified the boundary in the mid-19th century, this line represents a critical point in understanding the distribution of species across the Malay Archipelago and beyond.

The Wallace Line, stretching through the waters between Borneo and Sulawesi, and extending southward to the islands of Bali and Lombok, in Indonesia, delineates the sharp divide between species that are more closely related to Asia and those that have closer affinities with Australia.

History and location The concept of the Wallace Line emerged from Alfred's travels and field studies across the Malay Archipelago during the mid-1800s.

Wallace, who is also credited with co-developing the theory of natural selection along with Charles Darwin, was fascinated by the distinctiveness of the wildlife in these islands.