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Ottoia

life science Maturity 7-9 climate
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This was a small worm.

Ottoia tricuspida ROM 63057.jpg
Ottoia tricuspida ROM 63057.jpg
It lived in the sea. It moved through the mud. It used its mouth to find food. It was a hunter. Can you find it in the picture?

37 words

Ottoia was a worm that lived long ago.

Ottoia tricuspida ROM 63057.jpg
Ottoia tricuspida ROM 63057.jpg
It was about 8 centimeters long. It lived in the mud at the bottom of the sea.
Ottoia burrowing.jpg
Ottoia burrowing.jpg
The worm made a U-shaped hole to stay safe. It used its mouth to hunt for food. The mouth had sharp teeth and hooks.
Ottoia prolifica teeth NMNH 198591.jpg
Ottoia prolifica teeth NMNH 198591.jpg
It could even eat other worms like itself. This worm was a very good hunter in the deep sea.

79 words

Ottoia was a worm that lived a long time ago.

Ottoia tricuspida ROM 63057.jpg
Ottoia tricuspida ROM 63057.jpg
Most fossils of this worm come from the Burgess Shale. This is a place in British Columbia, Canada. These worms were about 8 centimeters long on average.
Ottoia burrowing.jpg
Ottoia burrowing.jpg
They lived in the mud at the bottom of the sea. The worm lived in a U-shaped burrow. This helped the animal stay safe. It could reach out from its hole to find food.

Ottoia was a predator, which means it hunted other animals. It used a proboscis to catch prey. A proboscis is a part of the body that can be pushed out. This part had sharp teeth and hooks.

Ottoia prolifica teeth NMNH 198591.jpg
Ottoia prolifica teeth NMNH 198591.jpg
The teeth helped it grab small animals. One animal it often ate was called Haplophrentis. This was a shelled animal. Ottoia also ate dead things. It might even eat other worms like itself. This is called cannibalism. The worm had a gut that ran through its body. It also had muscles to help it move.

174 words

Ottoia was a type of worm that lived a very long time ago.

Ottoia tricuspida ROM 63057.jpg
Ottoia tricuspida ROM 63057.jpg
These animals are known as stem-group archaeopriapulids. They lived during the Cambrian period. Most clear fossils of these worms come from the Burgess Shale. This famous site is in British Columbia, Canada. Scientists also find tiny fossils of them in the Western Canada Sedimentary Basin. Some fossils have even been found in China.
Ottoia burrowing.jpg
Ottoia burrowing.jpg

This worm had a very interesting way of working. It lived in a U-shaped burrow in the sea mud. The worm could push out a part of its body called a proboscis. This proboscis had many sharp teeth and hooks on it. The worm used these teeth to grab its food. It often ate a shelled animal named Haplophrentis. It would swallow these animals head-first. Sometimes the worms even ate other worms like themselves.

Scientists have studied these fossils to learn about the worm's body. On average, an Ottoia was about 8 centimeters long. Its body was divided into 70 to 100 rings called annulations. The body was bilaterally symmetrical, which means both sides look the same. However, the front part showed radial symmetry.

Ottoia sclerites - schematic.png
Ottoia sclerites - schematic.png
A tough outer layer called a cuticle protected the animal. Inside the body, a gut ran from the mouth to the anus. A group of muscles acted like a gizzard to help with food.

Many fossils were found because of how the worm lived. The Burgess Shale was at the foot of a high limestone reef. Mud could slide down from the cliffs in underwater avalanches.

Ottoia tricuspida ROM 63057.jpg
Ottoia tricuspida ROM 63057.jpg
This mud could bury the worms quickly. This helped keep many of them safe for millions of years. In one area called the Greater Phyllopod bed, there are 677 specimens. These worms make up about 1.29% of that animal community.

Learning about Ottoia helps us see how life worked in the deep past. It shows us how early predators hunted in the mud. Just like a modern worm might dig in a garden, Ottoia dug in the sea. It used its hooks at the back to anchor itself while burrowing.

Ottoia burrowing.jpg
Ottoia burrowing.jpg
Even though they lived long ago, they were very active hunters. They played a big part in the ancient ocean. Studying them helps us understand the history of all living things.

398 words

Ottoia was a stem-group archaeopriapulid worm that lived during the Cambrian period.

Ottoia tricuspida ROM 63057.jpg
Ottoia tricuspida ROM 63057.jpg
This ancient organism was a predator that lived on the ocean floor. It is famous today because of its many well-preserved fossils. Most of these large fossils come from the Burgess Shale in British Columbia, Canada. While some fossils are found in China, the clearest examples are from this Canadian site. Studying Ottoia helps scientists understand how early animals hunted and lived in ancient seas.

The body of Ottoia had a very specific structure. It was bilaterally symmetrical, meaning its left and right sides were mirror images. However, the front end, or anterior, showed radial symmetry.

Ottoia sclerites - schematic.png
Ottoia sclerites - schematic.png
A tough outer layer called a cuticle protected the animal and limited its size. The main part of the body, the trunk, was divided into 70 to 100 rings called annulations. These rings changed in spacing depending on how the worm moved or contracted. An internal nerve chord ran down the entire length of the organism.

Ottoia had a specialized way of eating using an eversible proboscis. An eversible part is something that can be pushed outward from the body. This proboscis was located at the front end of the worm. It was covered in an armature of sharp teeth and hooks.

Ottoia prolifica teeth NMNH 198591.jpg
Ottoia prolifica teeth NMNH 198591.jpg
Scientists have identified two different species based on these teeth: Ottoia tricuspida and Ottoia prolifica. At the base of the pharynx, a ring of spines sat near the teeth. Behind that, a series of hooks and spines were arranged in a quincunx pattern. This pattern looks like the five dots on a single die.

The worm used its body to live a very active life in the sediment. It was a burrower that likely lived in a U-shaped burrow.

Ottoia burrowing.jpg
Ottoia burrowing.jpg
To move through the mud, it used a series of hooks at its posterior, or back end. These hooks acted as anchors to hold the worm in place while it dug. From the safety of its burrow, it could extend its proboscis to find food. Inside the trunk, a gut ran from the anus to the mouth. A dense group of gut muscles functioned as a gizzard to help process food.

Ottoia was a fierce predator and a scavenger. Fossil evidence shows it often hunted a shelled animal called Haplophrentis. The worm typically swallowed these prey items head-first.

Ottoia burrowing.jpg
Ottoia burrowing.jpg
Gut contents also show that Ottoia practiced cannibalism. This means they sometimes ate other members of their own species. This behavior is still seen in modern priapulid worms today. By eating both other animals and their own kind, they played a major role in their ecosystem.

We know so much about Ottoia because of how it was preserved. The Burgess Shale was located at the foot of a high limestone reef. Underwater mud avalanches could slide down from the cliffs.

Ottoia tricuspida ROM 63057.jpg
Ottoia tricuspida ROM 63057.jpg
These slides would quickly bury the worms living on the bottom. This rapid burial prevented them from decaying and kept them intact. In the Greater Phyllopod bed, 677 specimens have been found. In that specific community, Ottoia made up 1.29% of the total animals.

Scientists have found many specimens in various collections. The University of Northern British Columbia (UNSM) holds at least 1,000 specimens. Other large collections exist at the Royal Ontario Museum (ROM). While some reports place Ottoia in places like Spain or Nevada, these are not considered secure. The only truly verified large fossils come from the Burgess Shale. However, tiny microfossils of their teeth are found throughout the Western Canada Sedimentary Basin. These tiny clues help map where these worms once traveled.

613 words
🖼️ Images & Media (4)
File:Ottoia tricuspida ROM 63057.jpg
Ottoia tricuspida ROM 63057.jpg
File:Ottoia sclerites - schematic.png
Ottoia sclerites - schematic.png
File:Ottoia prolifica teeth NMNH 198591.jpg
Ottoia prolifica teeth NMNH 198591.jpg
File:Ottoia burrowing.jpg
Ottoia burrowing.jpg
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