06/05/2026
🧬 DID YOU KNOW? The Mother Dog Shapes More Than Genetics — She Shapes Neurodevelopment Itself 🐾
One of the most common simplifications in dog breeding is the idea that temperament is “50/50” sire and dam, or that genetics alone determines behaviour.
The reality is far more biologically interesting.
Yes - both parents contribute genetically.
But the mother influences development in two fundamentally different ways:
👉 Genetic inheritance (DNA from both parents)
👉 Developmental programming (how that DNA is expressed)
And it is this second layer - developmental biology - where the dam has a profound and often underappreciated impact.
🧠 1. The womb is the first environment (prenatal programming)
Even before birth, puppies are exposed to their mother’s physiological state.
Through the placenta, the dam influences:
Cortisol levels (stress hormones)
Nutrient availability
Oxygenation
Immune signalling molecules
Epigenetic regulation of gene expression
This is known in developmental biology as foetal programming.
👉 Elevated or unstable maternal stress during pregnancy can alter the development of the puppy’s HPA axis (stress-response system), shaping how reactive or resilient that puppy may become later in life.
So temperament begins before the puppy ever breathes air.
🐶 2. Early neonatal regulation: the mother as the external nervous system
Once born, puppies are biologically immature.
They cannot regulate:
Temperature
Blood glucose stability
Stress responses
Emotional arousal
So the dam performs a critical role in co-regulation.
Through:
Warmth and contact
Licking (which stimulates autonomic regulation)
Scent familiarity
Nursing rhythms
The mother actively helps calibrate the puppy’s autonomic nervous system, teaching the body what “safe” feels like.
This is not behavioural learning in the traditional sense - it is physiological regulation learning.
🧠 3. Learning by observation begins immediately
While genetics provides potential, the dam provides the first behavioural model.
Puppies rapidly learn:
How to respond to novelty
How to recover after stimulation
How to interact socially
How to settle and rest
This is mediated by early social learning mechanisms, including observational learning and emotional contagion.
👉 If the mother is calm and environmentally confident, puppies are repeatedly exposed to low-arousal behavioural baselines.
👉 If she is highly reactive, those patterns become the puppy’s earliest reference for “normal”.
⚖️ 4. The “80% maternal influence” idea - what’s actually true?
It is not scientifically accurate to assign a strict percentage like 80%, but the concept behind it reflects an important truth:
The dam influences behaviour through:
Genetics (50% contribution, like the sire)
Epigenetic modulation of gene expression
Prenatal hormonal environment
Early postnatal neurodevelopment
Primary social learning
So while both parents contribute DNA equally, the mother uniquely contributes the developmental environment that determines how that DNA is expressed.
In developmental neuroscience terms:
👉 Genes load the gun, but early environment - heavily shaped by the dam - determines how the nervous system is calibrated.
🧬 5. Why this matters for temperament in Border Collies
In a cognitively sensitive breed like the Border Collie, early neurodevelopment strongly influences:
Environmental sensitivity
Arousal regulation
Problem-solving confidence
Recovery speed from stress
Social adaptability
These are not “trained in later” - they are developmentally scaffolded early.
💚 The Emerald Park philosophy
At Emerald Park Border Collies, we place significant emphasis on:
✔ Selecting stable, environmentally balanced breeding females
✔ Supporting low-stress, well-structured pregnancy environments
✔ Allowing calm, consistent maternal rearing conditions
✔ Understanding that temperament is built, not just inherited
Because we are not simply producing puppies -
we are supporting the formation of developing nervous systems.
🐾 Final thought
When you bring home a puppy, you are not just seeing the result of genetics.
You are seeing:
🧠 prenatal biology
🐶 maternal regulation
🧬 epigenetic expression
🌱 early social learning
All working together to shape the dog they will become.
And it all begins with the mother.
- Donna Williams,
Emerald Park Border Collies.
www.emeraldparkbc.com
"Guided by science.
Raised with purpose
