You’ve probably been exposed to one news headline or another in the recent past (let’s say the last 5 years) that reads something like “SCIENTISTS DISCOVER GENES THAT CAUSE (X).” X, of course, varies massively based on the study itself (and sometimes the bastardisation of said study by media): it can include describing medical conditions such as cancer, autism or congenital diseases; behavioural traits, such as sexual preferences; or broad physical traits, such as the classic problem of the inheritability of height. Unsurprisingly, you may think that trying to find the genes responsible for some traits should be either a) super easy, or b) super hard, depending on your own philosophical preference or the trait in question. So how do these studies come about, anyway?
We’ve spent some time before discussing the nature of the term ‘species’ and what it means in reality. Of course, answers to questions in biology are always more complicated than we wish they might be, and despite the common nomenclature of the word ‘species’ the underlying definition is convoluted and variable.
It shouldn’t come as a surprise to anyone with a basic understanding of evolution that it is a temporal (and also spatial concept). Time is a fundamental aspect of the process of evolution by natural selection, and without it evolution wouldn’t exist. But time is also a fickle thing, and although it remains constant (let’s not delve into that issue here) not all things experience it in the same way.
For anyone who has had to study geography at some point in their education, you’d likely be familiar with the idea of river courses drawn on a map. They’re so important, in fact, that they are often the delimiting factor in the edges of countries, states or other political units. Water is a fundamental requirement of all forms of life and the riverways that scatter the globe underpin the maintenance, structure and accumulation of a large swathe of biodiversity.
Earlier in the year, I had made a comment that, as part of the natural evolution of this blog, I would try to change up the writing format every now and then to something a little more personal, emotional and potentially derivative from science. I must confess that this is one of those weeks, as it’s been an emotional rollercoaster for me. So, sorry in advance for the potentially self-oriented, reflective nature of this piece.
Contrastingly, sometimes we might also use genetic information to do the exact opposite. While so many species on Earth are at risk (or have already passed over the precipice) of extinction, some have gone rogue with our intervention. These are, of course, invasive species; pests that have been introduced into new environments and, by their prolific nature, start to throw out the balance of the ecosystem. Australians will be familiar with no shortage of relevant invasive species; the most notable of which is the cane toad, Rhinella marina. However, there are a plethora of invasive species which range from notably prolific (such as the cane toad) to the seemingly mundane (such as the blackbird): so how can we possibly deal with the number and propensity of pests?
Tools for invasive species management
There are a number of tools at our disposal for dealing with invasive species. These range from chemical controls (like pesticides), to biological controls and more recently to targeted genetic methods. Let’s take a quick foray into some of these different methods and their applications to pest control.
The potential secondary impact of biological controls, and the degree of unpredictability in how they will respond to a new environment (and how native species will also respond to their introduction) leads conservationists to develop new, more specific techniques. In similar ways, viral and bacterial-based controls have had limited success (although are still often proposed in conservation management, such as the planned carp herpesvirus release).
The better we understand invasive species and populations from a genetic perspective, the more informed our management efforts can be and the more likely we are to be able to adequately address the problem.
Managing invasive pest species
The impact of human settlement into new environments is exponentially beyond our direct influences. With our arrival, particularly in the last few hundred years, human migration has been an effective conduit for the spread of ecologically-disastrous species which undermine the health and stability of ecosystems around the globe. As such, it is our responsibility to Earth to attempt to address our problems: new genetic techniques is but one growing avenue by which we might be able to remove these invasive pests.