Invertebrate Variation
The Earth Worm (Arctiostrotus perrier) has a slick body with no antenna or fins of any sort, this allows it to move easily around in the soil where it spends most of its life. Instead, they are covered in tiny hairs called setae (or chaetae) which provide more grip while still keeping the slick shape of the worm, allowing it to move under ground. Earthworms also have circular muscles around each length of body, these muscle groups are what allow worms to stretch and once again, move around under the soil. Many Earthworms also secrete a mucus (coelomic fluid) which help them easily move throughout the soil. In some species this mucus can harden into a tube to keep walls around them from collapsing, and in others it can even be toxic to soil bacteria and used as a defence mechanism. One myth is that Earthworms can be cut multiple times and will become many smaller worms as a result of evolution to their harsh environmental conditions. This is in fact not true, though a worm can survive being cut in half if the anterior (head) region is still intact, though the cut-off half of the worm will not survive.
Invasive Plant Species
Dandelions (Taraxacum) are a plant native to Eurasia and has since spread all throughout North America. They first arrived in Canada when European explorers brought it with them from their home countries. Dandelions are notorious for being able survive in harsh, tight conditions (think those cracks in the sidewalk with a yellow flower popping out). Dandelions can grow pretty much anywhere and a reason they are flourishing is because they grow back so fast. When in full cotton ball form, dandelions can spread seeds easily, and fast simply when the wind blows. These seeds spread around allowing the dandelion population to grow, and grow. Though they are not one of the most harmful invasive species to its environment, in fact it used to be thought of as part of a healthy full lawn as it can be eaten and used in natural medicines. It wasn’t until the second war when “perfect” lawns were the standard that these pesky plants became hated. They are especially hard to get rid of because of strong roots. They are also easily able to spread their seeds with in full form because of the many seeds that simply float around and create a new dandelion plant in the soil. They are considered invasive simply because they are so hard to get rid of. This means that many governments do not see it a big enough deal to take big action to get rid of dandelions. Instead many herbicide companies make certain spray chemicals targeting dandelions. Some people also prefer to go the natural route and pull the dandelions by hand, just don’t forget to pull from the root!
Sources
https://www.sciencelearn.org.nz/resources/17-earthworm-adaptations
https://www.bobvila.com/articles/how-to-get-rid-of-dandelions/#:~:text=The%20quickest%20and%20least%20labor,take%20a%20more%20natural%20route.
https://nationalpost.com/news/canada/dandelions-finally-get-their-day-in-the-sun