When people think of growth there are several processes that will come to mind, physical, economic, metaphorical. The Oxford dictionary defines growth as ‘the process in people, animals or plants of growing physically, mentally or emotionally.’ In this section we are going to be discussing about how escherichia coli and a mountain back gorilla grows over its life.

E. Coli

E. coli is referred to as a prokaryote which is an organism that lacks a nucleus and other organelles. The nucleus for e oil is not membrane bound and their genetic material floats over the cells cytoplasm therefore it falls under this category. The process E. coli goes through to grow is known as binary fission. This is form of asexual reproduction where a parent cell separates into two new daughter cells. This process happens via division and duplication of the parents genetic matter – with each daughter receiving one copy of the parents DNA.

Within this image you can see how the nucleus of the cell divides into two and therefore allows the original cell to create a genetic copy of itself.

The optimal conditions for E. coli to grow is typically 37c under aerobic conditions, however there have been found some strains that grow at 53c. The term aerobic here means that there is either free or dissolved oxygen present within the aquatic environment that the organism is living in. In this case, for E. coli, its most commonly found within the intestinal tract of healthy mammals.

The life cycle of E. coli varies depending on its environment as outside of the body it can be anywhere from hours to even months:

  • Inside of soil it can live for up to 130 days
  • Inside of a river for up to 27 days
  • Inside cattle of slurry for 10 days
  • On stainless steal for more than 60 days
  • At least 12 hours on wooden cutting boards

Wild gorillas are found in equatorial Africa separated by around 560 miles of the Congo Basin forest. Gorillas like to live in families of typically around 5 – 10 but can sometimes be as large as 50 which will be led by a single dominant adult male or otherwise known as a silverback who will hold his position for years. Females will typically give birth around every 4 to 6 years and will have no more than 3 or 4 children. It’s due to this low reproduction rate that the gorillas are struggling to recover from population declines. In fact both the gorillas species have been decreasing in population however through the efforts of conservations in 2018 such as the WWF gorillas have went from a critically endangered status to just endangered.

Mountain gorillas follow the same growth process as many other mammals. In most cases, when a female is sexually mature she will initiate the mating process with the dominant silverback. The pregnancy will last around 8.5 months in which the mother will provide hormones and nutrients for the foetus, much like us humans. A baby gorilla will be unable to walk for 3-4 months solely getting around via riding on its mothers back. For the next 3-4 years the infant will nurse from its mother and continue to develop. For the next 6-8 years the gorilla will go into its juvenile period in which it will grow to become more independent from its mother weening off her milk and starting the diet of a regular gorilla: berries, fruit and occasionally insects etc. The average weight of the gorilla at this time is around 68 kg (127 lbs) and it will be full of thick black hairs, making it hard to differentiate between genders. A female will reach young adulthood at the age of 8 to 10 years where as a male doesn’t reach this stage till 12 to 15 years. During this time the males will retain their black hairs therefore are known as blackbacks. This is the age that female gorillas finish their growing process around the weight of 113 kg (250 lbs) to 136 kg (300 lbs). However, for a male they will continue to grow into mature adulthood – the last stage of a gorillas life cycle. By this time the male will have developed it’s distinct silver hairs on its back and grow to an average height of 1.5 to 1.8 metres and weigh 204 kg (450 lbs) to 226 kg (500 lbs). This is the time that females  become sexually mature and are able to produce children, therefore restarting the cycle.

Within this image you are more clearly able to see the life cycle of a gorilla as it summarises everything we just talked about.


In the foetus stage of a gorillas life it shares some similarities to E. coli in which it lives inside of its mother sharing her nutrients and hormones in order to grow. Similarly to E. coli the foetus shares its parents DNA however it takes two parents to reproduce in gorillas. The reproduction in E. coli is an entirely asexual process. The process of growing a foetus is similar in that the cells will divide and duplicate to gain mass – however they remain united working together unlike E. coli. It will continue to do this until the foetus becomes a full baby and is ready to be born into the world.