North America 77 million years ago

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The Cretaceous is the 3rd and final period of the Mesozoic Era geological period that continued from about 145 to 66 million years ago.

It was a geologic period with a comparatively warm climate, resulting in high eustatic sea levels that shaped many shallow inland water bodies.

The Earth was ice-free, and forests stretched to the poles. Oceans and water bodies were populated with now-extinct aquatic reptiles, ammonites, and rudists, while dinosaurs remained to dominant on land.

Nevertheless, during this time, new groups of birds and mammals emerged. Birds became increasingly common and diverse. During the Early Cretaceous, flowering plants emerged and began to speedily diversify, becoming the leading group of plants across the globe by the end of the Cretaceous, coincident with the decrease and elimination of formerly widespread gymnosperm groups.

By the late Cretaceous (100.5–66 Million ago), the continents were startling to assume their broad contemporary alignment. The Americas were flowing westwards, making the Atlantic Ocean broaden. India was still in the initial stages of its northward journey, attached alongside Madagascar. Australia was still linked to the Antarctic fragment of the ancient supercontinent of Gondwanaland. Manchuria and China were yet to bump with Siberia, and the continents of the northern hemisphere were, as yet, detached from their southern counterparts by a sinuous Tethys Ocean. Snaking up from Tethys, the Western Interior Seaway cut across the North American continent.

During the Late Cretaceous, the climate was warmer than now, although, throughout the period, a cooling tendency is clear. The tropics became reduced to equatorial regions, and northern latitudes experienced considerably more seasonal climatic conditions.

In the Late Cretaceous, the hadrosaurs, dromaeosaurs, ankylosaurs, therizinosaurs, spinosaurids, pachycephalosaurs, and ceratopsians experienced success in Western North America and eastern Asia. Tyrannosaurs dominated the large predator niche in North America. In the northern hemisphere, cimolodont, eutherians, multituberculates, and metatherians were the predominant mammals.

Near the end of the Cretaceous Period, flowering plants diversified. In temperate regions, recognizable plants like magnolias, sassafras, roses, redwoods, and willows could be found in abundance.

The Cretaceous ended with the Cretaceous–Paleogene extinction crisis, a significant mass extinction in which many groups, comprising non-avian dinosaurs, pterosaurs, and giant marine reptiles, died out.

Below is the map of North America 77 million years ago. According to this map, In the Late Cretaceous, the many contemporary U.S. states were beneath the waves of the Western Interior Seaway. It’s fascinating that elevations and water levels have changed that much throughout millions of years.

Nowadays, you can see many marine fossils in the mountains of Colorado and New Mexico that 77 million years ago were at the bottom of the Western Interior Seaway.

Now let’s fantasize. Let’s look at what the 2020 U.S. presidential election map would look like if the position of the continents had not changed in 77 million years.

This map looks pretty different from the map of Trumpland and Biden archipelago.