https://www.space.com/alien-planet-k2-18b-water-vapor-not-earth-twin.html
K2-18b is 110 light years from Earth. Did K2 develop during the same time period that Earth did? K2 most likely has a similar EM field that the Earth does. Otherwise the solar winds from it's Dwarf Star would have blown the cloud layer away exposing the surface to the harmful Ultraviolet radiation leading to a more Mars like planet that would sublimate any water away from the planet over millions of years.
K2-18b is 2.3 times wider than Earth. With K2-18b also being 8 times as massive as Earth, K2-18b would have been able to clear the area of an dust forming around the Dwarf Star, thus adding the dust to its evolutionary processes. The amount of water on K2-18b based on its mass and width and that water vapor has been discovered in the atmosphere, could be comparable to being able to cover the Earth in water three times over. Under ground aquifers would lead from the near un livable oceans on the tidally locked side into pristine underground lakes as well as feeder lakes branching off of the underground lakes.
Therefore we can also speculate that the core of K2 is active, and the planet has considerable volcanic activity. In order for Earth to maintain its atmosphere the core has be active causing tectonic plate movement. With enough active volcanoes on K2 being active layers of volcanic ash spewed into the atmosphere would block a percentage of the Ultraviolet radiation from the Dwarf Star making life more likely. The layer of volcanic ash would be regulated so precisely that underneath of the layer of volcanic ash there could exist a primitive age of dinosaurs similar to the age of dinosaurs here on Earth.
At higher elevations, mountains would not have any ice or snow because the intense UV would melt most of the polar snow and ice on the side facing the Dwarf Star. As the frozen organics begin to thaw bacteria would thrive in these higher regions due to the amount of frozen organics thawing and becoming food. On the cold side not facing the Dwarf star thermal conveyance would transfer heat from the tidally locked side that would create near dark winters such as Alaska has. The further that you would travel to the exact point opposite of the Dwarf Star on K2 would create a year round darkness. Snow and ice would present but would eventually sublimate into the atmosphere creating clouds that would then evaporate into water vapors as the clouds crossed into the tidally locked side of K2. Because some of the clouds on the dark side of K2 would contain particles of ash along with organics making the water drop heavier, some of the water,when vaporized at the lower levels of K2, would create great regions of fog and mist that would provide an abundant source of nutrients and herds of reindeer along with predatory animals.
Tardigrade could also definitely survive at the higher elevations given their survival characteristics. Where there is water and organics there is surely to be Tardigrades. With the massive number of Tardigrades present higher evolved bacteria would be able to feed on the Tardigrades and so forth until a winged bird feeds on the snail. Tardigrades might even be the first life form encountered when collecting water vapor samples from the upper atmosphere.
https://en.wikipedia.org/wiki/Tardigrade
The side of K2 facing the Dwarf star would most likely be nearly un-inhabitable except under the cover of volcanic ash clouds where animals ranging from birds to reindeer would flourish. As the volcano ceased to erupt and spew ash the animals would seek the next volcano thus creating a migration patter similar to Humpback Whales that would include predatory animals who migratory patterns would either follow the herds or would go into a state of dormancy until the herds return. Or predatory animals could even have learned to evolve and did underground tunnels between each volcano to hunt the herds of animals taking shelter under the volcanoes protective ash cloud.
Some animals and insects that could exist on the Ultraviolet drenched K2 would be:
Butterflies, Reindeer, Birds, Black-Eyed Susans (flower), Bees, Sockeye Salmon and Scorpions.
https://www.theatlantic.com/technol...-can-see-or-glow-in-ultraviolet-light/243634/
The birds would feed on the Bees, Butterflies and other flying insects. The Bees would feed on the flowers creating large caches of honey that could reside between the most temperate point of the locked side and the dark side of K2. Or like the underground animals locked side bees could go dormant during each phase of a volcano returning. When the volcano they are living under becomes active, spews its ash and blocks out the UV radiation for a time. Flowers bloom, the Bees become active collect the pollen and make it into honey while pollinating the next phase of flower seeds. Bees that hibernate on the locked side of K2 would also provide underground animals and insects with source of nourishment in the form of honey and the bees themselves.
The seeds drop onto the ground and are eaten by birds and other insects or reindeer like animals. Some seeds would make it into a dormancy phase to grow again once the UV levels were lessened by the volcanic ash. From volcanic ash we would get carbon dioxide that plants and flowers along with microbes would consume to release oxygen as a waste bi-product.
Some bacteria that can create oxygen that grow only in the absence of oxygen, would be Clostridium, Bacteroides, and the methane-producing archaea (methanogens), are called obligate anaerobes because their energy-generating metabolic processes are not coupled with the consumption of oxygen. Oxygen can be produced from a number of materials, using several different methods. The most common natural method is photo-synthesis, in which plants use sunlight convert carbon dioxide in the air into oxygen.
UV radiation would have a severe and detrimental effect on the marine life of K2, especially on the tidally locked side of K2. Marine animals such as algae, corals, crustaceans, "Did somebody call?" Thanks, Sebastian the Lobster everyone, fish larvae and eggs would all die off thus greatly reducing the food chain for larger marine life such as the Sockeye Salmon. As we move towards the darker side of K2 and where volcanic activity along rising continents was the greatest is where we would see marine life flourish as the reduction of UV radiation would be prevalent.
....but what lives in the deeps of K2's tidally locked oceans and creeps in to feast on a passing pod of whales heading to their winter feeding grounds opposite the Dwarf Star is uncertain.
So there is a chance that animal, insect, avian, mammal and marine life does exist on K2.
Read more:
http://www.madehow.com/Volume-4/Oxygen.html#ixzz5zNVlfTyj
https://earthobservatory.nasa.gov/features/UVB
https://www.igsoc.org/annals/44/a44a162.pdf
