Speciation trash talk

Speciation trash talk

We all have psychological drivers, don’t we? Some are drawn to intellectual pursuits; others to looking and feeling good in their body; and some people openly admit that if they could just eat like a pig all day long, that would be the perfection of life.

Let me tell you a quick story…

Once upon a time, there was a person – Tina. She was particularly inclined towards an easy life. And boy did her dream come true. She liked to put her feet up and do as little as possible that could disturb her fun, so naturally, she was happy to hang around people who would just tell her what to do and what not to do. Appeasement was her middle name. Tina was incredibly trustworthy, and of course liked to let her hair down with her pals from time to time. Who doesn’t, after all?

Now let’s zoom in on Turner. Turner was a bit wilder. His enjoyment came from being out in nature and he could deal with some austerity. In fact, he was an avid hunter; getting thrills from chasing the vulnerable. Don’t get me wrong, he worked under an authority, but within that social structure, he was able to get what he wanted out of life.

We can see that Tina & Tuner’s living environments were intricately linked to their psychological drivers in life. As such, it would be a rare occasion that they happened to pass one another. Some say ‘opposites attract,’ however, Tina may well have thought, ‘not if you were the last dog on earth…’

…I do apologise if you were reading and expecting a Pride & Prejudice ending. Having said that, we’re about to explore how this could indeed be an alternate scenario.

(And yes, Tina is a dog; Turner is a wolf.)

Dogs, wolves and coyotes have all been placed into the Genus Canis. It used to be that dogs and wolves were classified as separate species, however, most sources now say that they are sub-species of the extant grey wolf, Canis lupus. Coyotes are counted as a separate species – Canis latrans.

This sounds like a done deal, however, one significant caveat is that coyotes and wolves are able to interbreed and produce fertile offspring (vonHoldt et al. 2016). To be classified as a different species, this should certainly not be possible.

To make matters more complicated, as wolves and other wild animals become accustomed to more efficient modes of dining that we have created as a by-product of our societal habits (anything from livestock to your upturned garbage bin), it seems that this can result in their resultant domestication (Newsome et al. 2017). For dogs, who are believed to have initially evolved from such a process (Li et al. 2014), could we once again be seeing the re-domestication of the grey wolf, and thus the ‘creation’ of a new dog?

The big issue here is that we can’t even agree as to what actually defines a species. For example, if two organisms cannot produce a fertile offspring, does this mean that they are separate species? But what if they could do, but are just not attracted to one another, or are not in close geographical proximity to one another? That is, in a narrow snapshot of time, can we really be certain that any two organisms of seemingly different species within a genus couldn’t produce fertile offspring? I think the honest answer has to be, ‘we don’t routinely carry out that experiment; therefore, we don’t know.’

According to our working model, what are referred to as different species are in fact rather psychological variants. Of course there are barriers to reproduction, however, these barriers are based on time, place and circumstance, and are reversible. The evidence is mounting in favour of this proposal because it more reasonably reflects the plastic nature of living organisms.

What we’re saying is that one can start with a car (genus), and this car can be modified in a number of ways (microevolution); however, there is no evidence for turning a car into an aeroplane. The term ‘species’ is man-made and doesn’t fit the available data. It is more plausible that what we refer to as species are in fact psychological variants within a genus, some of whom can quite happily interbreed to produce fertile offspring at a time and place when that becomes appropriate. And if it’s OK to say ‘evolution happens in long periods of time,’ then logically it should be equally valid to propose that ‘so-called species are able to mate, if given long periods of time.’  This is a testable hypothesis, making it falsifiable; whereas the theory of speciation is not falsifiable.

 Finally, you’re probably wondering what happened to our Tina & Turner duo; I can’t confirm for sure, however, it is likely that one starry night they will bump into one another whilst chowing down on your leftover cheese sticks and humous. Then who knows what little hybrid wolf-dogs may appear in your neighbourhood.

References

Li, Yan, Guo-Dong Wang, Ming-Shan Wang, David M. Irwin, Dong-Dong Wu, and Ya-Ping Zhang. 2014. “Domestication of the Dog from the Wolf Was Promoted by Enhanced Excitatory Synaptic Plasticity: A Hypothesis.” Genome Biology and Evolution 6 (11): 3115–21.

Newsome, Thomas M., Peter J. S. Fleming, Christopher R. Dickman, Tim S. Doherty, William J. Ripple, Euan G. Ritchie, and Aaron J. Wirsing. 2017. “Making a New Dog?” Bioscience 67 (4). Oxford University Press: 374–81.

vonHoldt, Bridgett M., Roland Kays, John P. Pollinger, and Robert K. Wayne. 2016. “Admixture Mapping Identifies Introgressed Genomic Regions in North American Canids.” Molecular Ecology 25 (11): 2443–53.