It has been proven in Australia that the invasive cane toads are taking a more direct approach to conquering the continent.
Rick Shine of the University of Sydney and his colleagues have managed to analyse 10 years of tracking data as the cane toads invaded the Northern territories.
The data showed that the first toads to arrive travelled in straight lines covering the ground quicker. The slower toads hopped randomly all over the place and got there three years later. The team then bred the speedy toads together* (nb* it was a quick process as they got straight down to it) and showed that the progeny of these faster toads followed more direct paths than the offspring of the slower parents.
Shine suggests that this inheritable trait could explain the accelerated invasion….
So if toads can have traits that enable them to invade quicker and more efficiently… are the various Japanese knotweeds at large in the UK showing variable speeds of ‘invasiveness*’ …?
Well the first thing to say is that the toads have sexually reproduced with a variable DNA base meaning that successive generations could breed in a particular benefit – whereas Japanese Knotweed has all been cloned from the original plant brought over to Kew in 1850 by Phillipp Von Siebold. Cloning means that each successive generation will have identical characteristics to its parent meaning that there would be no selection, improvement or variation in character.
What can be suggested by the data available is that Japanese Knotweed is moving its way further Northward in the UK and that it continues to grow both later in the season and start to produce buds earlier each year. This could be a symptom of milder winters, earlier Spring or even global warming?…
Watching Countryfile on TV a couple of weeks ago I noticed an article on ground dwelling bees which had become newly resident on the South coast – these bees had come over from Europe and were now making their way Northward.
What should be noted with all these cases is the adaptability of invasive non-native species. It bodes caution and awareness in all of us that if we see something ‘unusual’ then we should check and identify what it is you have seen – whether it be a plant or an animal.
….and watch out for those toads – they’re coming straight at you!
*Invasiveness – NOT A REAL WORD!