How Does Life Appear in the Most Extreme Places?
Since the dawn of planet Earth, organisms have evolved each day to adapt to their habitats and live. So many species have gone extinct, either from being hunted by apex predators or from natural selection. The latter one meaning that it is survival of the fittest, only those species, who have the necessary characteristics will survive. All of this was before humans introduced technology and their greed into planet Earth. It can be misunderstood, as I prefer to use technology for simplistic and boring matters, and I also appreciate all that humanity has achieved in terms of scientific and technological progress. But, it is one of the saddest things, to watch humanity's counterparts, animals struggle with their habitats being demolished.
How can animals be our counterparts? Well, the definition for a human being is an animal, who has a conscience and uses logic for its actions, even though instincts are still there, ready to kick in. Usually, instincts help humans in situations, where everything happens really fast, or so it seems at least. Although, some humans might not use their brains, so far, this is the accepted definition. The main issue remains the integration of technology with nature, which most of the time consists of nature getting the short stick. Pollution, deforestation, and many other problems caused by humans have directly impacted different species and their habitats. The picture of this polar bear, (Figure 1) to a normal human being, breaks their heart and serves as a reminder of the grim reality in front of them if they do not take precautions to stop destroying nature.
Despite all the destruction and the continuously reducing number of habitats, organisms continue to thrive, even in the most obscure and unexpected places. Fungi are living organisms that can grow in land and aquatic environments. Sometimes they can even grow in deserts. For many years, fungi were classified as plants and were placed into the Plant Kingdom. Though that classification was deemed as wrong after scientists found proof that these organisms were closer to animals. But, Fungi do not have a stomach, so they were placed into their own kingdom, known of course as the Fungi Kingdom. These particular organisms were found to live in the Dead Sea. The famous Dead Sea is located between Jordan and Israel, known for its saltiness. It is ten times saltier than ordinary seawater, which makes it impossible for anything to live there. Knowing that only microorganisms and algae can live in the Dead Sea, is an impressive feat. Three species of Fungi were isolated, with one of them being described as a new species, Gymnascella marismortui (Ascomycota). An experiment was conducted, where cultures from these species did not grow on agar media without salt. But, they grew on the agar prepared with at least 50% Dead Sea water. So, it may suggest that these Fungi are adapted to living in the hypersaline water that the Dea Sea provides.
Eurotium rubrum, a filamentous fungus is being studied by scientists for its ability to withstand large amounts of salt. Most living species in the Dead Sea, usually go dormant when overwhelmed with salt. But this filamentous fungus does well in the water itself. In an experiment conducted by the Israelian, German, and U.S. scientists, the Fungi specimen, in higher salinity levels stopped growing but survived. From this experiment, it was determined that at higher levels of salt, the cells were tightly locked so that salt could not drip into them. In comparison to other fungi or microorganisms, Eurotium tries to actively cope with its environment and does not fall dormant despite ceasing its growth process. The combined effort of these scientists consists of cracking the ability to withstand increased salinity levels so that crops with increasing desertification and salinity can grow in the future. They stated that:
“The observed functional and structural adaptations provide new insight into the mechanisms that help organisms to survive under such extreme environmental conditions, but also point to new targets like the biotechnological improvement of salt tolerance in crops. In principle this discovery could revolutionize saline agriculture worldwide by laying the groundwork of understanding necessary to appropriately using salt-resistant genes and gene networks in crops to enable them to grow in desert and saline environments,”
Recently, it was found that Fungi have been growing in Chernobyl. So many people might think, so what, Fungi grow everywhere. Below in (Figure 2), the Fungi can be seen growing in the wall of the reactor. Besides the fact that Fungi are growing in one of the most radioactive places still, how they feed themselves is an amazing feat, that humanity might use in the future. The Chernobyl Fungi, known as Cladosporium sphaerospermum, are converting gamma radiation into energy for themselves. This species of Fungi is using the melanin that it contains to synthesize energy for itself. Radiosynthesis is the name of the process. It is thought, that in the future these Fungi can be used to protect astronauts and space objects from radiation. Some scientists are also trying to use the melanin found in them to make sunblocking cream against the Sun's radiation.
Cactus is a plant, which has adapted itself to thrive in environments with little water. Usually, they are found in deserts and their root system is close to the surface and spread out in a large area, to suck up any water droplet. Cactus plants grow only when it rains, and as soon as the rains period ends, growth is halted. This is done in order to preserve as much water as possible, for the rest of the year. They are known for having spikes instead of leaves so that they do not lose any drop of water and to prevent any animal from snacking on them.
An interesting species of cacti plants is the Creeping Devil. They give the false impression of large worms with spikes on them (Figure 3) when it is actually just a plant of the cactus family. Scientifically is known as Stenocereus eruca, and also is endemic to a region of Mexico. Also, it is the only known moving cactus in the world. What helps the Creeping Devil migrate is its laid-down position, which also aids it in surviving in isolation. The Creeping Devil moves by growing horizontally from its stem, killing its rear end and sprouting new roots to absorb water and other nutrients while crawling through the desert. The rear end gets assimilated with the soil, which gives the roots back the nutrients and water it possessed. In a sort of poetic way, this unique cactus sacrifices a part of itself, so it can carry on its long voyage and nourish the living part. Usually, it travels slowly. Although, it is dependant on the climate where it grows. It has a sexual form of reproduction, but because of its self-isolation, it also reproduces by breaking part of itself. It creates new clones of itself, which grow and die as individual organisms. However, it has gone on the list of endangered species. The two main reasons being illegal trafficking and the agricultural industry. The first ones harvest these cactuses to sell them, as their prices can range from 4,000-5,000 dollars in the black market. That price is estimated to be for a single Creeping Devil stem. As per the agricultural industry, farmers destroy these colonies to make way for their cattle, which is a nuisance and barrier to them. The Creeping Devil can live to 100 years, if not interfered with.
Another weird creature lives inside underwater volcanoes' vents and can withstand the high temperatures of 750 Degree Celcius. They are known as volcano snails (Figure 4). Their nickname is "Sea pangolin", as they possess the ability to withstand high temperatures, pressures, acidity, and also low levels of oxygen. Its endurance to all those violent, nonfriendly conditions is attributed to its ability to incorporate iron into its shell. Scientists have called it the "origin of life" because they have decoded a genome, which shows the presence of a protein enhancing the tolerance to metal ions. This explains its ability to assimilate iron into its shell. They did not find the presence of any other unique genes, despite its unique ability. The volcano snail had the same genes present in mollusks. The excitement coming from this discovery is due to the hypothesis, that life may have begun from hypothermal vents. The snail's gene sequence has remained unchanged throughout its evolution, for more than 540 million years. Therefore, scientists believe that this study might shed light on how life evolved in past eras. Also, fun fact, it is the only known gastropod alive, that possesses scale-like armor. This was a very common feature for gastropods during the Cambrian era, over 540 million years ago.
In the face of all this permanent destruction and upcoming doom, life continues to thrive. Fungi living in the Dead Sea, life in death. Sounds poetic, but it is true, life can be found there. Fungi living in one of the most radioactive places on Earth, caused by human error, and finding a way to turn that poison into their strength. A plant that travels that has an adventurous spirit, the Creeping Devil. An intriguing cactus with a scary name, but unwilling to submit itself to extinction. And last but not least, a snail living in underwater volcanic vents. It stands guard like Cerberus does in Greek mythology. No mythical powers, just the simplest ability to diffuse iron into its shell, to protect itself from all the elements that may cause harm to it.
Source of the featured image:
The Scientist. (2015, February 1). Yellowstone National park [Photograph]. https://www.the-scientist.com/features/the-energy-of-life-36017
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