Rattus norvegicus
Rattus norvegicus or the brown rat is found primarily in human populated areas and thrive in low income/unplanned urban areas. With their original habitat being fields and forests. They are also very intelligent being trained to solve mazes and they use this intelligence to search for food usually eat humans wate products. They are often in contact with endo parasites like flies and ticks, while being predated on by cats, foxes, falcons and hawks to name a few. They also are hunted by humans who see them as pests and are often associated with pestilence. The diet of rats is that of human scraps (whenever they are in close proximity to them), berries and pet foods and excrement. Rats combat being constantly predated by having a fast gestation period of 21 to 24 days. They are also highly flexible and can fit into incredibly small places. While their teeth can chew through most common materials that humans use to build with. Rattus norvegicus grow anywhere from 30-50 cm (from head to body) with a tail length of up to 20cm and weighing anywhere from 200g to 500g. in the more temperate areas they tend to be on the larger side on the scale. They use there relatively large tails to help them balance in their rural environments they use it as a counterbalance and can help them grab into hard to climb surfaces, whereas in their urban environments they use the tails to allow them to use things such as powerlines as makeshift highways due to their relative safety.
Jason Munshi-South et al.
The evolutionary history of wild and domestic brown rats (Rattus norvegicus).Science385,1292-1297(2024).DOI:10.1126/science.adp1166
Alonso, R. et al. (2020) ‘Norway rat (Rattus norvegicus) ectoparasites in livestock production systems from central Argentina: Influencing factors on parasitism’, Acta Tropica, 203, pp. 105299–105299. Available at: https://doi.org/10.1016/j.actatropica.2019.105299.
amoeba proteus
amoeba proteus (otherwise known as Chaos diffluens) are found in well oxygenated freshwater usually around vegetation or on the bed of the water source where it feeds of other protozoa, algae, bacteria and small particles of dead animals and plants and nontoxic particulate matter. They are adapted to their active hunting lifestyle by using pseudopodia (a fake limb) that they use to ‘drag’ themselves towards a food source. This is an active form of transportation and thus means they require more food than they otherwise need to survive. When they catch there pray, they envelop them and start forming a food vacuole around the food source. Once they have fully enveloped their food, they begin to release enzymes to break down the food into more digestible nutrients. amoeba proteus is a ‘Giant’ protozoa and this means its main predator is a larger version of its own species. They are a microorganism with their largest members being up to 5mm in length, but the average specimen is 1 to 3mm in length.
Both species have their advantages and disadvantages they are pray to different predators and in different scales of living creatures. Both have adapted to be highly effective in their own ways weather it is using the giant relative size of the amoeba proteus or the agility and size of the Rattus norvegicus. Rattus norvegicus is often seen as a dirty animal meanwhile amoeba proteus is found in what most would assume to be dirty water as it thrives in stagnant or slow-moving fresh water.
References:
Kaneshiro, E.S. (1995) 45 – Amoeboid Movement, Cilia, and Flagella, ScienceDirect. Edited by N. Sperelakis. Academic Press. Available at:
https://www.sciencedirect.com/science/article/abs/pii/B9780126569704500518.
Gibbs, D. and Dellinger, O.P. (1908) ‘The Daily Life of Amoeba Proteus’, The American Journal of Psychology, 19(2), p. 232. Available at: https://doi.org/10.2307/1412761.