Humanity's population explosion and massive overconsumption of natural resources is killing off wildlife at an unprecedented rate. In the 2018 Living Planet Report by the World Wildlife Foundation (WWF) we come to understand that there has been a 60% decline in species population sizes since 1970. Especially hard hit are the tropics in South and Central America, which have seen a 89% loss compared to 1970. And freshwater ecosystems, like rivers and lakes, have experienced the largest decline of 83%. We have killed off 83% of all mammals and 50% of all plants since the dawn of civilisation, and its irreversible on human timescales. It is truly a biological annihilation as coined in a scientific study published by Ceballos et al. in PNAS last year.

In 2017 the world lost an amount of forest area equivalent to the size of Italy, destroying habitats, causing biodiversity loss and polluting the environment. There is a growing number of scientists that are now calling for a global deal for nature, creating vast nature reserves to prevent biological armageddon.

While climate change is a major threat to all species on Earth a new report published in Nature shows that overexploitation and agriculture are the two biggest culprits of biodiversity loss.

75% of all the plant, amphibian, reptile, bird and mammal species that have gone extinct since 1500s were caused by humans. A growing global population will only put other species under more pressure, and eventually impact human mortality too.

Biodiversity underpins all ecosystem services (e.g. climate regulation, flood protection, pollination, nutrient cycling, water purification etc) that we currently consume "for free" but will have to replace with costly infrastructure or restoration project once they are gone.

Now that we are reaching limits to what these ecosystems are able to withstand without collapsing or drastically altering states we will see a steep increase in costs for the most basic of resources. Those costs are often dumped on the public by the private sector and may not turn up in prices of goods but instead in  form of increasing taxes, poorer health, growing debts etc.

It is truly a sad fact that most people are so disconnected from the land and oceans that they are blind to the fact that Earth's resources are finite. Once a fish stock has collapsed it may never recover, on a timescale relevant to us.

There is no "replay" button that we can magically push and turn back to some previous healthy state. All we can do now is to minimize the damage. And the best way to do that is by not having more kids than we can feed and not consuming more than we actually need for basic needs.

For a decade now it has been widely debated whether humanity has set in motion a sixth great mass extinction event, comparable to the catastrophe which erased the dinosaurs some 66 million years ago. According to a recent study by Ehrlich et al. (2015) there is no longer any doubt, we truly have.

There is general agreement among biologists that extinction rates have reached levels unparallelled since previous mass extinctions on Earth. However, some have believed the numbers to be overestimated. But this new study confirms that species are disappearing up to about 100 times faster than the normal rate between mass extinctions, known as the background rate. If allowed to continue, life would need millions of years to recover.

The study took a precautionary approach and only allowed for conservative estimates, which means that their calculation probably underestimate the severity of the extinction crisis.

As human population continues to grow and consumers become more affluent more and more natural habitats will be altered or destroyed. Already in 2005 scientists warned that about 60% of all ecosystem services had been degraded or destroyed (Millennium Ecosystem Assessmentt). The long list of impacts include: land clearing for farming, logging and settlement, invasive species, carbon emissions that drive climate change and ocean acidification and toxins that alter and poison ecosystems. 

While there is still much discussion about the causes of some mass extinctions, it is generally believed that they can occur when the biosphere is under long-term stress, for example from a warming climate generated by greenhouse gasses in the atmosphere. As ever more species face extinction we lose the vital ecosystem services they provide, such as: pollination, water purification, pest control, storm control, soil regeneration etc. For its continued existence mankind is reliant upon an untold number of species that maintains the function of those services. As these species disappear, that existence becomes increasingly fragile.

Stanford biologist Paul Ehrlich calls for fast action to conserve threatened species and habitat before the window of opportunity closes. Below is a video from Standford with Ehrlich describing the issue.

One elephant is murdered every 15 minutes for their tusks. More and more conservationists and NGOs have become aware of the connection between elephant poaching and terrorism. Both species extinction and global terrorism are two major issues to the international community. Both involve the loss of innocent life and require urgent action.

Now the director of Hurtlocker and Zero Dark Thirty, Kathryn Bigelow, and the writer of Contagion and An inconvenient truth, Scott Z. Burns, have made a 3 minute animated short movie called “Last Days” that depict this connection and why it matters. Because many experts believe that elephants in the wild could go extinct within a decade the moviemakers chose to make an animated piece for a broader audience that could be released quickly. Despite there being plenty of graphic images on the internet of elephants being slaughtered, the killing continues. The short movie is an attempt to focus the viewer on the trail of money as well as the trail of blood. 

African terrorist organisations like Al Shabaab and Boko Haram use money from poaching to fund their activities. This is one of the reasons why elephant poaching has increased dramatically over the last years and become “industrialized”. Buying trinkets made out of ivory thus contributes both to species extinction and funding of terrorism. Illegal wildlife trade is the fourth biggest black market in the world, only surpassed by narcotics, arms trade and human trafficking. 

As a result of this movie a new foundation called www.lastdaysofivory.com promotes awarness and cultural change towards ending illegal ivory trade though encuraging people not to buy any ivory (see icon on the right). Other organisations have similar campaigns but that often does not include the terrorism connection. For example, the Chinese retired NBA basketball player Yao Ming has contributed to the cause of trying to get the Chinese to stop buying ivory by figuring in short information videos with elephants. By focusing on the terrorism connection, however, conservation organisations can gain more traction from the government to implement regulations since national security is of higher priority than environmental protection.  

Hydrogen sulfide (H2S) is a colorless gas that is heavier than air, smells like rotten-eggs and very poisonous to most organisms (including humans). It results from bacterial breakdown of organic matter in the absence of oxygen, a process known as anaerobic digestion. H2S is very toxic to local marine organisms, fish die in low-oxygen (anoxic) water. The production of H2S is believed to have been one of the contributing causes to pre-historic mass extinctions (Ward, 2007). The theory is that global warming (CO2 increase in the atmosphere) lead to a slowdown in ocean currents as the temperature gradient between the poles and equator diminished, which in turn led to anoxic conditions that produced massive quantities of hydrogen sulfide, killing off vast amounts of plant and animal life. However, last year scientists found that dissolved H2S, in very small doses, can also have a growth effect on plants (Dooley et al. 2013). If correct, we may have found a way to enhance yields without using petroleum, which would be a major breakthrough for humanity. 

The biological effects of H2S have received increasing attention during the last decade. Not only as a considered kill mechanisms during past mass extinctions but also as an important signalling molecule in organisms. While high levels of gaseous H2S kills plants, extremely low levels of liquid H2S seem to trigger a growth spurt. The origin of these dual activities remains unknown but scientists suggest it might be remnants of biological responses by life evolving in highly anoxic environments of earlier times in Earth’s history. Studies into the effects of sulfide compounds on plants are still few and most have focused on the lethal effects. It is known that H2S causes inhibition of photosynthesis at high concentrations but less is known about what happens at lower exposure.

A group of scientists at University of Washington reported in 2013 that by exposing plants roots or seeds to very low concentrations of dissolved hydrogen sulfide at any stage of life caused significant increases in biomass, including higher fruit yield. The study found that germination success and seedling size increased in bean, corn, wheat and pea seeds. They also found that time to germination in seeds treated with H2S was significantly less than values observed in untreated seeds (see figure below)

Enhanced growth rate continued for seven days after a single exposure, followed by a return to the slower growth unless re-exposed. The H2S exposed plants reacted with cellular divisions, increasing the absolute number of chloroplasts per area. One hypothesis is that H2S does not increase growth rates as a byproduct of the addition of sulfur as a “fertilizer”, as seen through the addition of phosphates or nitrates, but actually impacts cellular replication and photosynthesis. This rapid growth behaviour may have been selected for as toxicity decreases with larger plant size. While this research is recent and further studies are needed, this could have large implications for agriculture and biofuels.

“Biodiversity is the totality of all inherited variation in the life forms of Earth, of which we are one species. We study and save it to our great benefit. We ignore and degrade it to our great peril.” — E.O. Wilson

State of global biodiversity

Biological diversity (i.e. biodiversity) reflects the number, variety and variability of living organisms. It includes diversity within species, between species, and among ecosystems. The concept also covers how this diversity changes from one location to another and over time. Indicators such as the number of species in a given area can help in monitoring certain aspects of biodiversity. When one wants to understand the health of an entire ecosystem, however, some species may be more important than others in the sense that they provide a key function within the entire system. Ecologist often refer to such species as keystone species. Take for example the otter. They are considered a keystone species because of their critical importance to the health and stability of nearshore marine ecosystems. Otters eat sea urchins and other invertebrates that graze on giant kelp. Without sea otters, these grazing animals can destroy kelp forests and consequently the wide diversity of animals that depend upon kelp habitat for survival (Fig. 1). Additionally, kelp forests protect coastlines from storm surge and absorb carbon dioxide from the atmosphere.