Visiting an alien planet... on Earth

-

 


Visiting an alien planet... I don't know how else to describe the experience of exploring underwater. "Alien" can be defined as "coming from another world." To a terrestrial, air-breathing, homeothermic bipedal hominin, being underwater can only seem like being, well, on a different planet. There's a reason astronauts train in a pool to experience "neutral-buoyancy" diving to simulate the weightlessness of space travel. And creatures have been evolving in Earth's seas for a LONG time. Complex life appeared in the Earth's history about a half billion years ago.

"The basic body plans of all modern animals were set during the Cambrian Period, 542 - 488 million years ago."

Since then, species have come and gone (mostly gone), but if you visit a thriving reef environment, you won't even think about what has disappeared, because there is just so much still there!

This week we (Caroline, Wes and Mignon) went on a dive trip in the Caribbean Sea around Cozumel and in the cenotes near Tulum, in the Yucatán.

Cenotes are surface connections to subterranean water bodies. They are formed from the dissolving of limestone bedrock, followed by a collapse of the roof. 

Stalagmites and stalactites were formed when ocean levels were lower during the ice ages, then filled with water as the sea level rose.

We started off with 3 dives in various cenotes, including the Pit, then Dos Ojos (the Barbie line), and Dos Ojos (the Bat Cave line). "Lines" refer to the ropes you needed to follow to avoid getting lost. These were all cavern dives as opposed to cave dives. When cavern diving, you have to be able to see natural light the entire time that you are exploring the cavern, as opposed to a cave dive where no sunlight penetrates. Cavern diving it may have been, but when you put your palm over your flashlight, it was dark!











In the 100+ foot deep cenote "The Pit", you swim through a halocline layer at around 50 feet (where a body of freshwater sits on top of salt water, where you wonder what has happened to your eyesight), and just over a smoky hydrogen sulfate layer (sulfuric acid). Diving in fresh, salty, and hydrogen sulfate water... alien!


Then we took the ferry to Cozumel to dive in the Arrecifes de Cozumel National Park. Wesley took some great photos.














If Mignon is your dive buddy, she is unmistakable!


Visiting an alien planet...





Comments

Post a Comment

Popular posts from this blog

The Tale of the Maui Mystery Cat

-
Image
In 2003, a jaguar was suspected of terrorizing residents of the Olinda area, Maui. Photo of a jaguar attacking a cayman in the Pantanal, Brazil, by Frank Schoen. Copyright: https://www.123rf.com/profile_djambi1969 . Used with permission.      In 2003, I was sitting in a Starbucks across from the Honolulu Zoo in Waikiki, reading the Honolulu Advertiser , when I came across an article about the sighting of a large, cat-like creature on Maui. I don't have that initial article, but I did find an archived copy of an article from Hawaii News Now on the topic: Wildlife officials are planning to intensify efforts today to capture a large catlike animal spotted in the lower Olinda area of Upcountry Maui. A search team sent out yesterday found evidence the animal does exist. They discovered tree trunks with deep scratch marks and a number of doves that appeared to be killed by a catlike paw. Wildlife experts plan to bait an existing trap today and add four more traps. Officials say they be
Read more

The one, the only... Chobe National Park, Botswana!

-
Image
We were on our way to the famous Chobe National Park, in northern Botswana.  This visit was somewhat troubling for me.  In May, Botswana's president had announced an  end  to a five year ban on elephant hunting.  Elephant hunting?  There were calls for a boycott against Botswana.  Botswana is a bright spot for African savannah elephants, with over 100,000 in the country.  The proposal was to permit around 400 elephants to be killed by trophy hunters, who presumably would pay $30-50 thousand dollars to kill each of these animals (at $40,000 each, that would come out to $16 million).  There's roughly an equal number of elephants being poached for their ivory each year in Botswana.   I'm going to editorialize on hunting elephants for a moment.  Just scroll down to the white rhino photo below to skip my ramblings. But the overall populations of both forest and savannah elephants in Africa are in steep decline (especially with forest elephants ). And did you catch th
Read more

Cougars killing and eating people. Why?

-
Image
This cougar was killed after  attacking two mountain bikers in Washington, killing one.   On May 19, two mountain bikers were riding near North Bend, Washington, when they noticed a mountain lion (also called a cougar or puma) was following them.  I don't have the full details, but I've read that they stopped, yelled, put their bikes between them and the lion... things that almost all lion experts recommend to discourage an attack.  The lion persisted, however, grabbing one cyclist by the head, then chasing the other cyclist as that cyclist ran away.   T he first cyclist attacked got back on his bike, escaped, and called for help.  The second cyclist, Sonja J. Brooks, tragically, was found dead. “They stopped to confront the cougar, they did everything right, everything that we counsel people to do,” WDFW Captain Alan Myers said . “Do not play dead — fight back. Fight back with everything you’ve got,” he said. “In most instances, people survive attacks f
Read more