Competition Nature
Beginning of live
After formation of protocells, LUCA – Last Universal Common Ancestor, Anaerobic Prokaryotes ~4.0–3.5 billions years ago.
In the dim light of Earth’s ancient oceans, nearly 3 billion years ago, a microscopic revolution was brewing. Enter the cyanobacteria - tiny, blue-green architects of our planet’s future.
These primitive bacteria had evolved a remarkable ability: photosynthesis. Unlike their contemporaries, cyanobacteria could harness the power of sunlight to split water molecules, using the hydrogen to build their bodies and releasing oxygen as a waste product. It was an innovation that would change the world. At first, the oxygen they produced was quickly absorbed by the oceans and reacted with iron, creating vast deposits of rust that we now call banded iron formations. But the cyanobacteria were relentless. They multiplied, spreading across the ancient seas, their numbers growing exponentially.
Gradually, over hundreds of millions of years, oxygen began to accumulate. It saturated the oceans, oxidized the exposed rock, and finally started to bubble up into the atmosphere. This marked the beginning of the Great Oxygenation Event, around 2.4 billion years ago.
The change was dramatic. Oxygen levels in the atmosphere rose sharply. This new, reactive gas wreaked havoc on the existing ecosystem:
- It oxidized atmospheric methane, a potent greenhouse gas, plunging the planet into a series of intense ice ages known as the Huronian glaciations.
- It reacted with minerals in new ways, changing the very chemistry of Earth’s surface.
- A protective ozone layer formed high in the atmosphere, shielding the surface from harmful UV radiation.
For the anaerobic organisms that had dominated Earth for over a billion years, this oxygen-rich environment was toxic. They faced a stark choice: adapt, hide, or die. Many couldn’t cope, leading to one of the largest extinction events in Earth’s history - sometimes called the Oxygen Catastrophe.
But as some doors closed, others opened. The newly oxygenated environment created opportunities for life forms that could tolerate or even harness oxygen. These organisms evolved more efficient metabolisms, using oxygen to extract more energy from their food.
This shift set the stage for an explosion of diversity. The additional energy provided by aerobic respiration allowed for the evolution of larger, more complex life forms. It paved the way for the emergence of eukaryotic cells, multicellular organisms, and eventually, the diverse array of plant and animal life we see today. In a twist of evolutionary irony, the descendants of those early cyanobacteria - modern-day plants - would come to dominate the land, continuing to pump oxygen into our atmosphere.
Competition Nature
At the heart of life’s grand narrative lies a simple truth: the pursuit of resources. From the tiniest microbe to the mightiest redwood, from the depths of the oceans to the peaks of mountains, every living entity is engaged in an endless quest for the materials and energy needed to survive and reproduce. This fundamental imperative has shaped the course of evolution and continues to drive the dynamics of life on Earth.
Examples:
- Lions killing hyenas (and vice versa) to eliminate competition for prey
- Plants releasing allelopathic chemicals to inhibit growth of competing plants
- Male elephant seals fighting for breeding territories, sometimes to the death
- Invasive species outcompeting and displacing native species
- Human kill each other for resources (World War)