🌤️ Causes of Variation

Variation is central to life itself. Variation is what makes every single individual… an individual. Without variation, the evolution of different species would not be possible. What is the cause of variation?



Genes dictate what proteins our body makes, when, where and how, and are ultimately responsible for the way we look and function. It’s not just what genes we have though, it’s also about whether they are switched on or off, when they are switched on or off, and in which particular cells they are switched on or off. Us and chimps share a great deal of our genotype (genetic makeup), more than 98%, yet we can agree that there are significant differences between us that make us distinct species.


Features such as height, predisposition to illness, height and weight, or even behaviours such as risk-taking have been linked exclusively or partly to certain genes.



The environment is not just what most people associate with the word. It’s not just the temperature of the room you live in – it’s everything outside our bodies which exert their influence on it. Which is pretty much everything from family to friends, to the internet and to diet, exercise, culture and beyond. The environment in the womb where we grew had an impact on our bodies. Even the environment of genes themselves has an impact on…

🏆 Read 500+ topics for all 6 UK exam boards 🏆

📝 Enter now to claim your FREE 3-day trial and find answers to all your revision topics 📝
✔️ Just £3.49/month after that ✔️ Scholarships & teacher plans available ✔️ Cancel anytime

You explain everything so simply! 🙂 -SecretDuck on The Student Room
Just a huge thank you for spending your time helping others. I love your site and I’m seriously very grateful. No word of a lie -Neuron13 on The Student Room
Thank you for making all the content btw! -Serena Kutty on YouTube
Good topic notes and cool videos. I’ll definitely recommend it to my students. -Seema Sehgal (AQA Examiner and Biology Teacher) on LinkedIn