Introduction

Fourteen million years ago (14 MYA), a warm climate with higher CO₂ levels at 400-600 parts-per-million (ppm, 0.04-0.06%) created a golden age for life. Forests, coral reefs, and animals thrived in places like the Alps and Andes. Today’s climate, with 420 ppm CO₂ (0.042%), is milder by comparison. Using clear data, I’ll show how these ideal conditions fourteen million years ago supported a vibrant world of plants and wildlife. This glimpse of nature at its best sets up my later pages on our planet’s strength today.

Defining Biodiversity

Biodiversity: Number of differing species, like various plants and animals, in a region, though the total species count is often unknown (Mora et al., 2011).

Confusion Over Biodiversity The term “biodiversity” sounds scientific but is often used deceptively. It refers to the number of different species—like birds, fish, or trees—in an area. Scientists guess there are ~8.7 million species globally, yet only ~150,000 are studied, leaving most unknown (Mora et al., 2011; IUCN, 2023). Alarmists claim massive “biodiversity loss” to scare people, but without full species counts, these claims are shaky and subjective. Fourteen million years ago, the Miocene’s warm, CO₂-rich climate supported countless species, showing nature’s resilience despite such uncertainties.

Artist's depiction of giant camels that roamed the forests on Canada’s islands such as Ellesmere Island above the Arctic Circle. Then the Pleistocene Ice Age settled in 3.4–3.5 million years ago and the camels and forests were gone.

Artist's depiction of giant camels that roamed the forests on
Canada’s islands such as Ellesmere Island 3.4–3.5 million years ago.

Around 3.4–3.5 million years ago, during the mid-Pliocene warm period, giant camels (Paracamelus) roamed boreal forests on Canada’s Ellesmere Island. Fossil leg bones from the Fyles Leaf Bed site, discovered between 2006 and 2010, reveal a camel 30% larger than modern ones, standing 2.7 meters tall and weighing ~900 kg. Collagen fingerprinting linked it to dromedaries. The Arctic, 14–22°C warmer than today, supported larch forests where these camels browsed, aided by wide feet and fat-storing humps for snowy winters. By ~3 MYA, the Isthmus of Panama closed, blocking Pacific-Atlantic water flow and strengthening the Gulf Stream. This increased moisture transport to the Arctic, promoting precipitation and ice formation, contributing to Northern Hemisphere glaciation by ~2.6 MYA. As cooling reduced forested habitats, giant camels were likely gone from Ellesmere by 2.6 MYA, facing extinction or migration. The isthmus closure was a key driver of this gradual Arctic cooling, alongside declining CO2 and orbital cycles, transforming the region’s ecology. This explains the camels’ disappearance, contrasting with later North American camelids.

A Warm, CO₂-Rich Climate

Fourteen million years ago (14 MYA), CO₂ was at 400-600 parts-per-million (ppm, 0.04-0.06%), higher than today’s 420 ppm, based on fossil plant clues (Kürschner et al., 2008). The Earth was 4-6°C warmer, about 14-16°C globally (Zachos et al., 2001). Rainfall was 20-50% higher, making the world lush (Herold et al., 2010). This warm, CO₂-rich climate was perfect for life, supporting thick forests and many animals.

Forests and Animals Flourished

Dense forests covered the Alps, like today’s lower hills, and the Andes had rich woodlands during the Miocene (Graham, 2009). Extinct primates, like early chimpanzees, roamed the Alps, while ancestors to llamas, alpacas, etc., grazed in the Andes, alongside rodents and other mammals (Agustí et al., 2001). The Miocene’s warmth and ppm CO₂ fueled a high number of species, with no signs of climate problems. Animals and plants thrived.

Bikini Atoll corals recovered after 23 nuclear detonations between 1946 and 1958.

Bikini Atoll corals recovered after 23 nuclear detonations from 1946 to 1958.
See image Bikini Atoll bomb craters from space.

Coral Reefs Teemed with Life

Coral reefs in the Pacific were bursting with hundreds of species, supporting fish and sea creatures in the Miocene (Wilson, 2008). The warm climate and higher ppm CO₂ helped these reefs grow strong, with fossil clues showing no major losses. The Miocene’s mix of warmth, rain, and CO₂ made it a hotspot for marine life, far more vibrant than today’s oceans.

Different Oceans and Continents

Fourteen million years ago, continents and oceans looked different. South America was not yet joined to North America, letting ocean currents flow between the Pacific and Atlantic (Duque-Caro, 1990). Antarctica had less ice, and warm currents reached far north, boosting rain and warmth (Herold et al., 2010). Australia sat closer to Antarctica, and a vast sea linked the Indian and Atlantic Oceans, supporting rich marine life (Rögl, 1999). These open oceans and shifting lands created a lush, warm world, unlike today’s cooler, more separated continents.

Plato thinking.

Conclusion

The Miocene’s ideal climate—400-600 ppm CO₂ (0.04-0.06%) and 4-6°C warmer—created a paradise of forests, reefs, and animals in the Alps, Andes, and beyond. Its unique oceans and continents fueled this diversity. Today’s climate, at 420 ppm CO₂ (0.042%), is milder but still supports life, as my next pages show. The Miocene proves nature thrives with more CO₂ and warmth. Read my next page to see why today’s climate is no threat.

References

Evidence based Earth Science

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