After Billions of years First time Two Lifeforms merged into One

An international team of scientists has made a groundbreaking observation of an evolutionary event between a species of algae commonly found in the ocean and a bacterium. 

• This event has led to the merger of the two lifeforms, resulting in a single organism. 
• This is the first time in at least a billion years that such an occurrence has been witnessed. 
• The scientific journals Science and Cell have published the papers containing the details of this research. 

Endosymbiosis

Primary endosymbiosis, a process that has only occurred twice in Earth's history, gave rise to complex life through mitochondria and plants. 

In this process, algae engulfed a bacterium and provided it with nutrients, energy, and protection, while the bacterium gave the algae the ability to "fix" nitrogen from the air. The bacterium became an internal organ, or organelle, vital to the host's function.

Importance of discovery

Scientists from the US and Japan have discovered something that could change the way we think about evolution and agriculture. 

They found a new perspective on nitrogen fixation, which could help us understand how to add this to crop plants. 

This is important because the earliest life forms we know of were very small organisms called microbes. These microbes left behind evidence in rocks that are 3.7 billion years old. They produced a type of carbon molecule that only living things can make.

Early Life on Earth – Animal Origins

• Earth's earliest life forms were microbes that left behind carbon molecules in rocks about 3.7 billion years ago. 
• These microbes also created hard structures, called stromatolites, that date back to 3.5 billion years ago. 
• Stromatolites are made of sticky mats of microbes that trap and bind sediments into layers. A durable structure was created by precipitation of minerals inside the layers, even as the microbes die off. Today, scientists study living stromatolite reefs to better understand Earth's earliest life forms.
• The earth's environment, for most of its history, lacked oxygen and was high in methane. Therefore, it was not a welcoming place for animals. 
• Animals require oxygen to extract energy from their food. However, today, we live among diverse communities of animals that feed on each other, and our ecosystems are structured by feeding relationships.
• During the Cambrian Period, 510 million years ago, Earth's oceans had a diverse community of animals. This community included a top predator called Anomalocaris. By the end of the Cambrian period, almost all the major groups of animals we know today had evolved. 
• An illustration of animals near the ocean floor 510 million years ago depicts a large squid-like creature hovering over smaller organisms. The illustration was created by Karen Carr of Smithsonian.
• Illustration of animals near the ocean floor 510 million years ago. A large squid-like creature hovers over smaller organisms.
• During the Cambrian Period 510 million years ago one of Earth’s ocean communities, including the top predator Anomalocaris depicted.