Animals that are living fossils are animals that have existed for a long period of time, but because the environment changed they survived. The Archaeocyathids were found to be surviving from the Cambrian.
The Cambrian was 542 million years ago and they were found in South Africa. These organisms had no intrinsic mineralized tissue and were believed to be extinct over 3 billion years ago.

They were designed with an opening that was used for feeding. There were about 1000 species of these organisms and they grew to be 10 cm in length. They were believed to have a huge impact on the marine community because they could consume phytoplankton quickly.
The Coelacanth is found off the coast of South Africa and is one of the rarest sharks in the world. It was believed to be extinct until it was found alive in 1938. The biggest threat to these animals is humans because we are taking their homes and eating them.
The Tuatara lizard is also an animal that has been referred to as a living fossil; it is found only on New Zealand. These animals were living around 200 years ago and they were able to become 60 centimeters long. Their habitat is now limited to islands in New Zealand and an island near Australia due to the introduction of dogs by humans.
The Pikaia gracilens is another animal that has been referred to as a living fossil, it was discovered in Canada in the year 1880. They lived from 542 million years ago to 360 million years ago. These animals were about 10 cm long and had a small mouth which was used for feeding because they have no teeth.

The Helicoprion is another animal that has been considered as a living fossil; it was discovered in Russia in the year 1851. These animals were first found during the age of rocks, which were about 450 million years ago to 570 million years ago. The nickname for these animals was “Sabertooth shark”.
They had sharp teeth that are made from a mineral called magnetite. They are believed to have been able to hunt in groups and swim quickly.
From the years 400 million years ago to 450 million years ago there were primitive sharks that have been found to be surviving until today. They are considered as a living fossil because their bodies stayed the same but their brains evolved overtime. These animals had sharp teeth and hunted for prey in groups; they swam slowly through the water.
They were believed to have been extinct about 360 million years ago but in 2004, a well-preserved fossil of these animals were found. The name for this animal is Chlamydoselachus anguineus and they are able to live in salt water and fresh water. They can grow up to three meters long.
There were many species of these animals and they would hunt in groups which made it easier for them to catch their prey. They are believed to have been able to dive deep into the sea due to their flexible spine.

They were also designed with large teeth and sharp jaws that allowed them to consume their prey quickly. The biggest threat towards these animals is humans, we have been eating them for food since the year 2700 BC.
It is important to keep in mind that we are the biggest threat to these animals. We have been eating them for food since 2700 BC and hunting them for a number of other reasons. It is our responsibility to make sure that we are helping them thrive and not having any harm come to them.