There are many species that exist in the world. We see it in the diversity among the numerous environments we explore, from deserts to icy tundras. We know that there were many species that have gone extinct throughout the history of the Earth. And yet, we are not close to discovering many of the species that currently exist. In 2011 study done by researchers from Dalhousie University, Halifax, Nova Scotia, they found that there may be about 8.7 million species on Earth at the moment.
About 2.2 million of those species are marine life. They achieved this number by analyzing the current taxonomic grouping of species, which followed a consistent pattern. This pattern helped them arrive at their number. Knowing how many species are already discovered, the researchers estimate that 86% of land/avian species and 91% of marine species are still undiscovered by humans. While this number is prediction that needs continual research to support, it is an improvement from previous predictions that made many assumptions and ranged from 3 million to 100 million species. The bigger question now is where are these unknown species?
From the Mundane To the Extreme
Finding a species is a difficult and lengthy process. When you start looking, you are combing through numerous species that are already discovered and you might even miss out on a new species because it is similar to an already discovered species and you did not notice. But the first question that one has to ask is where should they start looking? The answer ranges from exotic ventures in the Amazon to your backyard. In 2011, two scientists found three new species of mushroom in their grocery store because they were mixed in with other mushrooms. New species have been found in backyards, cities, and the countryside. This is usually because these new species are small to the size of microscopic, like bacteria.
Besides those mundane areas to find species, scientists are keen on searching for species in extreme environments because finding life in those areas provides key insight into cellular functions under such stressful environments. They also provide information on how life could exist on other planets, with similar environments. One such extreme environment is hydrothermal vents. These vents spew highly toxic matter into the surrounding area, ranging from sulfur compounds to ammonia. They are also extremely hot and generally harmful to most life. Despite this, there are many species that coexist with these vents as they have developed ways to convert the chemicals that spill from it into energy to survive. There are also species that live in extreme cold, high salinity, high and low pressures, and even highly radioactive environments.
The species that live in these areas are called extremophiles. They are simply organisms that are capable of living in extreme environments that most other species would die from. They are a diverse group that holds special purpose for scientists. These extremophiles are potential representations of what life could be like in other extreme environments, like Mars or Europa.
The Hidden Ecosystems of Antarctica
Recently, the Larsen C Ice Shelf in Antarctica has broken and piece of it has begun to drift away. While the news of any major piece of ice formation breaking apart is terrible and important to understand as it relates to things like climate change, the broken ice shelf also presents an invaluable opportunity for scientists. The broken ice shelf has revealed 2,240 square miles of seafloor that was kept isolated from the outside world for over 120,000 years. This seafloor had no contact with the open ocean and no light source. This isolated ecosystem presents the best place to analyze life because of how similar the conditions might be to places like the ocean beneath the icy surface of Europa.
The organisms that live here would be similar to those deep within the ocean floor. They would also be a few extremophiles that are adept at living in very cold environments. Given the location of the shelf, it will take scientists a long while to reach the seafloor to study it. The British Antarctic Survey (BAS) is planning on sending research vessel as early as 2018. They are also competing against other scientists to be the first to study that area. The other major factor working against them is time. Now that the seafloor is exposed to the rest of the world, it will begin to change as organisms, such as plankton, begin to interact with the previously isolated ecosystem. This will lead to contamination that researchers will have to sort through to get a proper understanding of isolated ecosystems in the Antarctic.
Not much is known about the isolated ecosystems beneath the Antarctic ice shelves because there were only two other exhibitions prior to this in 1995 and 2002. Besides these ice shelves and hidden seafloors, the Antarctic does also hold hidden lakes with their own isolated ecosystems. In 2012, Russian researchers had drilled into Lake Vostok to study its ecosystem. Lake Vostok was isolated from the world for over 15 million years. That time frame is staggering and would allow considerable evolution to occur. Isolating lifeforms from the lake and comparing to life from the rest of the world would provide important information on how isolated lifeforms develop as well as how different evolution might occur for them. It would also offer much greater insight of life on other planets because of the length of its isolation. The scientists did collect samples and claimed that they found DNA that differed from any bacteria that we know. The central controversy surrounding this is the high risk of contamination that might have occurred.
Cross section of how the drilling occurred on Lake Vostok. Image from Wikipedia.com by the National Science Foundation, is licensed under CC0
Additional research would be needed to remove any information that occurred due to contamination so that we can get an accurate picture of life in the Lake Vostok. As we continue to examine the Antarctic region, we may find other lakes and isolated areas that could further increase our understanding of life on Earth and the length that life goes to survive.