The deep sea is a mysterious world. Until recently, figuring out how ecosystems down there evolved has been a challenge. Scientists have a hard time since not many fossils are found here.
The good news is that this is changing. Rewriting the history of the deep sea is now possible. However, scientists are now turning to trace fossils instead, which are signs of activity left by organisms. This approach has led to some fascinating discoveries.
We now know that the modern deep-sea ecosystem as we know it didn't just pop up overnight. It took a long time to develop during the Ordovician period. This coincides with a global cooling trend and an increase in oxygen levels. This seems to indicate a positive feedback loop. Bioirrigation from burrowing organisms helped oxygenate the sediment, which boosted oxygen levels.
Now the Ordovician period wasn’t yesterday, so let's understand what is going on. The Ordovician period is about 445 million years ago. The earth had just emerged from the ice ages during the Ordovician period. This event is also known as the Snowball Earth event.
The formation of deep-sea ecosystems has been an interesting journey. Let's consider the burrows of the deep-sea creatures. Burrows by deep-sea creatures are a fascinating observation. It turns out that the formation increases oxygenation. The increase in oxygen back during the Ordovician period has significant impact on the sustainability of a bait. This are all interesting but it is important to understand causation. What drove these changes? This is where paleontology meets climate science.
Just like the constant battle between the Earth's climate and temperature. The climate in the sea is different than on land. During the Devonian period there was another major climatic event. This event laid the foundation of the deep sea as we know it today. This is all due to oscillations in oxygen levels which has roots originating from climate-controlled oceanic circulation.
The deep sea really is an amazing place and scientists are still learning how it all came to be. Understanding the connection between deep-sea burrowing creatures, and the climate.