Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.
Greetings everyone. I hope you’re enjoying your summer. I thought today we’d take a little excursion into the wonderful world of plants, because without them we wouldn’t be here.
I still remember how astounded I was when I learned as a little kid just how old some trees were. The oldest animals can be 100 years old, but the sequoias and the bristlecone pines can be thousands of years old. There are trees in California that were alive when the world belonged to the Roman Empire and even some that sprouted back when the pharaohs ruled Egypt. But according to some recent research, the sequoias and the bristlecone pines are just babies. Read on!
We all know what sphagnum or peat moss is. It’s that stuff that they put in some potted plant containers. There are several different species and researchers studying the one that’s native to Hawaii have made some astounding discoveries.
First of all, they found out that the entire Hawaiian population of the peat moss Sphagnum palustre is a clone from a single parent. All the plants have been produced by vegetative rather than sexual reproduction and they are all essentially the same plant. But here’s the real kicker. That plant has been around for some 50,000 years.
The researchers say that surprisingly, the genetic diversity of the Hawaiian clone is about the same as the diversity found in sphagnum populations that do propagate sexually and occur in much larger regions.
That’s interesting because it indicates that that significant genetic diversity can develop in a clonal population. It also suggests that vegetative propagation can lead to long-term evolutionary success in a plant. Yup, I’d call 50,000 years pretty successful!
But that’s not the only ancient plant. Researchers from Australia have been studying another plant that’s pretty familiar to us here in the Marianas and they may have just found the oldest living organism on the planet. They’ve been studying seagrass.
Like the Hawaii peat moss, the gigantic seagrass Posidonia oceanica found in the Mediterranean, reproduces asexually and generates clones of itself. Researchers have found that a single plant can be up to nine miles wide and weigh more than 6000 tons.
But that’s not the real news. The researchers say that single enormous organism could be over one hundred thousand years old. Just imagine. A single plant that began growing when our ancestors lived in caves. A single plant that survived an ice age. A single plant that was alive when mammoths and saber-toothed tigers roamed the land.
Seagrass beds are the foundation of key coastal ecosystems but they don’t seem to be doing well with global warming and human pollution. Posidonia oceanica meadows have been declining for the last 20 years and are now shrinking at an estimated rate of five per cent annually.
So, the seagrass plants have survived for 100,000 years. But can they survive us?