Why Epigenetics Matters in Animal Behaviour

Epigenetics is the study of how life experiences – such as stress, nurturing, or socialisation – can influence gene expression without changing the DNA sequence itself. In companion animals, this means that early environments can shape lifelong behaviour by turning genes “up” or “down” like a volume dial.

While most epigenetic changes are not inherited genetically, they can have long-term effects on an individual’s behaviour, particularly when they occur during critical developmental windows (Mukherjee, 2016). Although we currently cannot test for or target these changes directly in animals, understanding epigenetics helps explain why early-life care is so vital – and why behaviour is more than just “bad training” or “bad genes”.

What Is Epigenetics, and Why Should We Care?

At its core, epigenetics refers to changes in how genes are expressed – without altering the underlying DNA sequence. Think of DNA as a book: the words remain the same, but epigenetic markers act like bookmarks or coffee stains that affect readability (Yong, 2009). These changes can be triggered by environmental factors such as stress, diet, hormones, and early-life experiences (Kolata, 2015).

Genetics vs. Epigenetics

  • Genetics is the actual DNA sequence that determines protein production.
  • Epigenetics affects how much or how often genes are used.
  • Genetic differences change what a protein does.
  • Epigenetic differences alter how much of that protein is produced.

Traits like shyness or confidence can result from the same genes being expressed differently due to life experience (Zimmer, 2015).

How the Environment Rewrites the Script

Early life experiences can “tune” gene expression. A classic study found that baby rats raised by nurturing mothers became more resilient, while those raised by less attentive mothers were more anxious. This behavioural change was linked to epigenetic – not genetic – differences in brain gene expression (Wastell & White, 2016).

Can Epigenetic Changes Be Passed Down?

Although rare, some epigenetic changes can be passed to the next generation. However, most epigenetic markers are wiped at conception. This means that offspring generally start with a clean slate, and their own experiences shape their gene expression (Zimmer, 2015b).

What This Means for Companion Animals

  • Early-life environments significantly impact behaviour.
  • Animals from stressful backgrounds may develop lasting fear or anxiety.
  • Socialisation can shape gene expression in beneficial ways.

However, changing ingrained behaviours is complex and not always straightforward.

Can We Reverse Epigenetic Changes?

Possibly, but we don’t yet fully understand how. Epigenetic markers can change throughout life, and behaviour modification or medication may help. However, reversing specific epigenetic changes directly isn’t currently feasible (Berezow, 2016).

The Future of Epigenetics in Animal Behaviour

Imagine diagnosing or treating behavioural issues using epigenetic insights. While promising, the science is still limited by challenges such as accessing brain tissue and understanding complex behavioural pathways (Zimmer, 2016).

Final Takeaway

Epigenetics adds a vital dimension to our understanding of behaviour. It demonstrates that early experiences shape biology – not just learned responses. Creating safe, enriching environments for young animals is one of the best investments in their lifelong wellbeing.

References

Berezow, A. (2016, January 27). End the hype over epigenetics & Lamarckian evolution. Big Think. https://bigthink.com/think-tank/end-the-hype-over-epigenetics-lamarckian-evolution/

Kolata, G. (2015, February 18). Project sheds light on what drives genes. The New York Times. https://www.nytimes.com/2015/02/19/health/scientists-shed-light-on-circuits-that-control-genes.html

Mukherjee, S. (2016, May 2). Same but different: How epigenetics can blur the line between nature and nurture. The New Yorker. https://www.newyorker.com/magazine/2016/05/02/breakthroughs-in-epigenetics

Wastell, D., & White, S. (2016, July 5). Epigenetics, rats and foetal programming: Making the “good enough” 21st-century mother. Discover Society. https://discoversociety.org/2016/07/05/epigenetics-rats-and-foetal-programming-making-the-good-enough-21st-century-mother/

Yong, E. (2009, October 12). What is the difference between the human genome and a pair of headphones? Not Exactly RocketScience. http://scienceblogs.com/notrocketscience/2009/10/12/what-is-the-difference-between-the-human-genome-and-a-pair-of/

Zimmer, C. (2015, March 8). Is most of our DNA garbage? The New York Times. https://www.nytimes.com/2015/03/08/magazine/is-most-of-our-dna-garbage.html

Zimmer, C. (2015, December 8). Fathers may pass down more than just genes, study suggests. The New York Times. https://www.nytimes.com/2015/12/08/science/parents-may-pass-down-more-than-just-genes-study-suggests.html

Zimmer, C. (2016, July 2). Growing pains for field of epigenetics. The New York Times. https://www.nytimes.com/2016/07/02/science/epigenetic-marks-dna-genes.htm