When justifying the conservation of species and biodiversity there are several key arguments frequently put forward. Maintaining functioning ecosystems, to ensure the provision of ecosystem services (i.e. ecosystem functions which benefit human such as removing CO2 from the atmosphere), preventing the loss of species with potential medical benefits and aesthetic and spiritual concerns are the main reasons frequently given in scientific literature, conservation organisation media and government publications. A final reason is often given or alluded to – existence value, the idea that because a species does exist it should be allowed to continue to exist. Does a species have a value which is not related to its benefit to humans (real or hypothetical) or interactions with other species? Many people certainly feel strongly that it is wrong to allow or cause the extinction of a species but when arguing the case alternative justifications for preventing species loss are heavily relied upon. The term “species” will be used to discuss this topic – however, the definition of a species and if this is the best level of diversity at which to conserve are debated topics.
Us and them
All of the main reasons, listed above, given for conserving species can be reduced to either those which are beneficial to humans in some way or those which concern the existence value of a species. Many of the arguments concern conserving diversity of life rather than the survival of individual species but all are ultimately underpinned by either one of these main ideas.
(Humans can be considered part of ecosystems and so perhaps the arguments cannot be divided in this way – but the extent to which humans are considered part of nature is a topic for another post!)
Conserve for human benefit
Conserving species in order to continue ensure the continued provision of ecosystem services is a reason to save species explicitly for human benefit. It does not actually support the conservation of all species, only those necessary for these services to continue plus several more species to make sure the ecosystem is robust enough to continue to provide the service despite some inevitable species losses.
Preventing extinctions to avoid the blunder of permanently losing a species with currently unknown medicinal properties is also clearly for the benefit of humans. Another human-orientated argument is conservation for aesthetic purposes, so that future generations can enjoy nature.
This does not detract from the use of these arguments to drive conservation effort; they are all important and valid points. In addition, human-based reasons may be the only arguments some will accept and the support of all kinds of people with different opinions is vital for successful conservation. But is there a greater moral reason to conserve?
Conserve for existence value?
Other arguments for saving species are more ambiguous in their motivations.
Defending conservation of species for spiritual reasons, although still orientated around human welfare, hints at a desire to care for nature as something beyond a mere resource for our use and benefit.
One of the strongest arguments for preventing extinctions is the (much debated and researched) idea that higher biodiversity results in a greater number of ecosystem functions – i.e. a more robust ecosystem which can cope with change. As with the ecosystem services argument, this reason is concerned with biodiversity rather than saving individual species. However, this argument can be split into the same two sides, human benefit and existence value. Conserving biodiversity in order to protect ecosystem functioning can be seen in one way as identical to the human benefitting ecosystem services argument. But on the other hand, “ecosystem functions” are distinct from “ecosystem services” for a reason – ecosystem services are defined as those ecosystem functions which are beneficial to humans. (Of course, the dividing line between the two is not as clear-cut as this as the complexity of ecology means it is not always obvious which functions are indirectly linked to those which we directly benefit from, but for the sake of argument we can treat them as separate motivations for conservation.)
So, to what end to we aim to protect the remaining ecosystem functions? Protecting biodiversity for the sake of robust ecosystem functioning means that more species can survive. If not humans, then the implication is that the beneficiaries of the ecosystem functioning argument are the species which could survive as a result. Here is the idea that the more species surviving, the better.
This leads to the question of existence value, the idea that because a species exists there is an ethical argument for its continued existence. Is this the case? Does anything affect this value? Does it matter if humans are the cause of the risk to a species’ survival?
The useless species
In order to illustrate the removal of all human-benefit reasons for conservation to leave only the question of existence value, an imaginary “useless species” can be used.
Imagine a species. As a species, it does no harm nor good to any other species (including humans). The ecosystem can carry on as before with or without it. This species does not deplete the numbers of any others and it not required to keep another’s population size under control. Nothing depends on it such that they could not survive as well on another species in its place. From a practical point of view, it does not matter to humans, other species, the ecosystem or the planet if this species lives or dies.
If this species is about to go extinct, is there an ethical reason to try to save it? Why? Imagine thousands and millions of these useless species – does this change anything?
Gut feelings
The origins of ethical values are complex and debated, but many if not most people feel that it is wrong to allow a species to go extinct, all other factors being equal, and feel so particularly strongly when humans have played a role in driving a species to a high-risk state. Why do we feel this way? Perhaps part of the explanation is a vague uneasiness about the finality of extinction – that it should be prevented in case a better reason is thought of after it is too late. Perhaps also because we feel that we are a part of the natural world and have a desire to protect it in a non-speciesist manner – most humans would not want our species to go extinct.
Gut instincts can be useful to help us understand why we feel an action is right or wrong but they are not an ethical argument. Is there a true ethical reason to save a species from extinction?
What is the existence value?
Existence value and the value of life
When debating the value of life, the experiences of the being and its ability to view itself as an entity with a past and future are considered, among other factors. Can these arguments be applied to a species? A species is not a conscious, pain- and pleasure-experiencing entity, the removal of which may result in a reduced level of enjoyment in the world. This may be true of the lives of individuals of sentient species but not of the species as a whole. Similarly, it is only genetics which drive the survival of species, but the fact that genetic material in a species is self-replicating is not a basis for ethical decisions about species. Genes around today are here because they evolved in a manner which caused them to survive; this does not mean that they have interests to consider. Individuals in a species may have a desire to survive but this is not true at the species level.
The way in which an extinction could result in a reduction of pleasure in the world is through its relationships with other species. One extinction is likely to have knock-on effects and could ultimately reduce the level of satisfaction and happiness of sentient beings by making survival tougher, for example through the loss of a key food source. This indicates that the value of a species is at least partly related to its role in supporting the happiness of sentient species – bringing us dangerously close to the anthropocentric arguments! However, this reasoning does not describe true existence value of a species, only additional considerations.
Taxanomic considerations
From an ethical, non-taxaist viewpoint it does not matter what kind of species is being considered, the question of an existence value remains the same. It feels different to consider the value of the useless animal than to consider the value of the useless bacteria, but this is due to the additional considerations related to the value of sentient lives and also our human-orientated aesthetic and spiritual feelings towards nature. Any existence value of a species is independent of these values.
Human destruction considerations
Extinctions happen. Species go extinct all the time in their millions and have done so since species evolved from the soup of the early Earth. In certain periods throughout the history of the planet there are mass extinction events when, for some reason or another, the extinction rate jumps significantly above the general base rate. We are currently experiencing a mass extinction event.
Does this change the existence value of a species? If a species does have a value then does it only extend to the end of the period it would have existed without the onslaught of recent human destruction? If this is the case then humans have a moral obligation to prevent the extinction of species which they have pushed to the edge of survival, because otherwise we are preventing the continued existence of a self-replicating species which has a right to continue to survive.
(NB The status of human actions as distinct from natural causes of mass extinction events, such as ice ages and meteors, is debateable!)
Pure existence value?
The above argument only suggests that if a species is assumed to have an existence value then we ought to prevent its extinction if we would be its cause. What is the essence of the existence value of a species? A species is a set of living beings which reproduce to create similar beings capable of further reproduction. Species around today have survived through many different forms and only exist in a transient state, constantly evolving. In this way a species is difficult to pin down as an entity which might have a right to survive. It is difficult also to consider the question of its continued existence without thinking of humans, the likely cause of its extinction.
Does a species as it exists at a given time have a right to survive? This right must be limited to the difficult to define or determine “natural lifespan” of the species as otherwise there would be a moral obligation to prevent any species extinction, including those which would have occurred anyway, and the world would be overrun with immortal species. Perhaps it has a right to continue to exist simply because it has done so, but why? Here is where this train of thought ultimately leads and so this discussion is not over – I would really welcome any opinions on this topic!
