What is an extreme environment?

An extreme environment is a habitat with harsh environmental conditions. Generally defined as somewhere that is challenging for humans and the majority of common organisms to survive.

Are significant changes really happening?

There is a lot of disbelief surrounding climate change and the reality of how the planet is really being affected. Organisms live and die, that is the natural order of things and organisms are very resilient; capable of surviving via evolution and adaptation to catastrophic changes in an environment, look at the life on this planet even after the mass extinction of dinosaurs. Animals now live in every environment on the planet, they have had to evolve to do so. So, what makes this any different?

Well, there isn’t talk that the world will end. That can be said definitively. Major other implications would be needed for that to occur. But one extinction of a species, no matter how small the knock-on effects, is an absolute tragedy.

Significant changes have already happened and is still ongoing. Animals have already been driven this far by anthropogenic (human) actions. Everyone has heard of the infamously extinct bird – the Dodo, hunted so much it no longer exists on this planet, besides as a fossil.

Four animals (including the Dodo) that have become extinct as a result of anthropogenic effects. (Sourced).

There are many more examples, but thats before everyone’s lifetime and nothing can be done about it now, yet there are current events occurring right before our eyes.

“Any fool can know, the point is to understand” – A quote by Albert Einstein that is very fitting.

Climate change effects

There is evidence that changing climate is causing problems that will have potentially drastic consequences for organisms in their natural habitats, at the current rate at which environmental conditions are heading.

Scleractinian (stony or hard) corals are hermatypic, which means they are responsible for reef-building. These corals are different than other types of coral due to their ability to build coral reefs. The one major difference is that these hard corals are primary producers as well as the carnivorous predators that non-hermatypic corals are.

Diagram of the anatomy of a coral polyp, with zooxanthellae and nematocysts presented.(Sourced).

Hard corals have symbiotic algae within their polyps, called zooxanthellae, which enable the corals to obtain sunlight energy via photosynthesis. Photosynthetic capabilities enable the corals to initiate the formation of a reef without the presence of other organisms because they aren’t reliant on prey.

Bleaching of corals is an important issue, as it is becoming too frequent and altering the environment for organisms inhabiting reefs. Bleaching is the result of the zooxanthellae being ejected (corals lose their colour and turn white), therefore rendering the corals unable to photosynthesise and without protection, and coral tissues will eventually die.

Diagram of the effects of thermal stress on corals. Coral bleaching and death occurs rapidly in reaction to an increase in temperatures of the water, and whilst it can be reversed, takes much longer period to do so. With current climate rates, unless something changes, reversing the bleaching before tissues die becomes less probable. (Sourced).

Zooxanthellae are important as they don’t just provide photosynthetic energy but also provide protection for the coral polyps from the Sun’s ultraviolet rays, by absorbing and converting the solar energy the corals aren’t exposed to the negative effects that UV rays have (degrade the proteins within cells), therefore without them, the coral is exposed and will most likely perish if thermal stress is prolonged.

The death of corals results in knock-on effects. Coral reefs have the highest species diversity on the planet, holding a greater diversity of species than rainforests, and much like if you demolish a forest, the inhabiting species lose the shelter the habitat provides. An example of an environment becoming more extreme, as the inhabitants are having to associate with more challenging conditions.

Contrast between the colours and life of a healthy coral reef (left) and a bleached reef (right). Left photo and right photo taken by Gary Bell and Roger Grace, respectively. (Sourced).

Conversely, increased temperatures are sending marine organisms towards the poles, where originally, the colder waters would be too extreme. This is an equilibrium effect, where one condition will cause an opposite reaction, by beginning to render a current extreme environment more hospitable to the majority of organisms.

The less extreme conditions that poles are becoming subjected too will not necessarily cause animals physical issues, as they are still cold enough for animals such as mammals not to overheat, however, the behavioural responses to the frozen habitat will be. Ice is melting, resulting in ice sheets breaking up and shrinking in size, plus a fewer frequency of ice floes. This affects all marine mammals that utilise both land and sea, for example polar bears, seals and walruses require rest to regain energy because if they run out, they will assuredly drown.

A severely thin polar bear unable to find sufficient prey, if any at all, which likely will not have survived. A grim future for polar bears if climate is allowed to continue at such rates. (Sourced).

Another consequence is that the polar bears, the ultimate arctic predators, are starving. The reduced cover of ice, grants seals and other prey a much greater access to water for escape causing polar bears to search for much less readily available prey on land, where there is not enough food to support the abundance of large creatures.

Environments are definitely becoming more extreme towards the current habitats, the acceleration of which is difficult to quantify as a result of so many different factors at work. Current environments at this moment in time haven’t become too extreme to cause complete habitat shifts – toppling the current balances within ecosystems.

Are organisms capable of adapting to environment?

Animals definitely have the capacity to evolve with fluctuating conditions and adapt to new environments, but the question that has needed an answer for some time now, is:

Will the animals adapt?

print

(Visited 43 times, 1 visits today)