What is Inheritance?

What is the difference between inheritance and evolution?

elephant seal lying on a beach with head raisedEvolution describes changes in inherited traits over time and through successive generations. That length of time can be very long, as in the case of the evolution of the elephant seal which took place over 25 million years.

Evolution can also be very short. In the case of Dr Endler’s guppies, evolution took place in just over a year in only 15 generations of guppy fish.

male guppy not brightly coloured with yellow splodgesInheritance is not the same as evolution; we will describe inheritance as those traits that you inherit from your own parents.

So what traits could you inherit from your parents? The emphasis is on the words ‘could’ because it is by no means certain that you will inherit any of these traits.

What traits could you inherit?

  • What traits have Bart, Lisa and Maggie inherited from each of their parents, Homer and Marge?!

Bart, Lisa, Maggie,Homer and Marge Simpson standing with their pets

The list of traits you could have inherited from your own parents is a long one, but here are a few examples….. You inherited two eyes but what color are your eyes?….

different eye colours including blue, brown, grey and green

You inherited a nose, but do you have an ‘aquiline’ nose with a prominent ‘bridge’?

woman with an 'aquiline' nose with a prominent 'bridge'

 You were born with a chin but do you have a ‘dimple’ on your chin?…..

chin of a man showing the dimple in his chin

You were born with two thumbs but do you have hitchhiker’s thumbs?…..

woman hitching a lift showing the hitchhiker's gesture

man pressing thumbs against each other demonstrating his hitchhiker's thumbs

You inherited two eye lids; do you have folds of skin covering the inner corners of your upper eye lids?….

Epicanthic folds showing folds of skin covering the inner corners of upper eye lids

You were born with ten toes but do you have second toes that are longer than your big toes?…

Morton's Toe showing second toe longer than big toe

You were born with a tongue, but have you inherited the ability to roll your tongue like this?…

boy showing 4 pictures of him poking his tongue out in 4 different clover leaf rolls

You were born with hair, but have you inherited a widow’s peak? (a widows peak is a ‘V’ shaped point in the hairline in the center of your forehead)

girl smiling showing her widow's peak

You were born with earlobes, but have you inherited ‘unattached’ earlobes (picture at upper left) or ‘attached’ earlobes (picture at bottom right)?

a variety of ears showing attached and unattached lobes

What color hair were you born with? Which parent did you inherit your hair color from? Will your hair turn gray as you get older just like your father’s and mother’s hair did as they grew older?

a variety of people with different hair colours including black, brown, red, blond and grey

Did you inherit a crooked ‘pinkie’ (little finger) from one of your parents?

a hand with 5 fingers with a crooked pinkie or 'clinodactyly'

Were you born with freckles?…

two heavily freckled girls smiling

Human Inheritance- ‘disabling’ conditions

Sometimes people inherit conditions which are seen by some people in society as somehow ‘disabling’. Some of these conditions are more ‘disabling’ than others. A few of these ‘disabling’ conditions are mentioned below: Some people are born with too many fingers or thumbs. A condition known as ‘polydactyly’.

Left hand with four fingers and two thumbs- a condition known as 'Polydactyly'

Other people inherit ‘color blindness’. A person who is ‘color blind’ might see this number below as ’21’ or may not see a number at all.

Ishihara colour blindness test- normal sighted people see number 74. This young boy has inherited ‘autism’, a developmental condition which harms people’s ability to communicate and relate to others. Autistic people often exhibit repetitive behavior. This young boy shows autistic tendencies by feeling the need to lay all his toys out in a row before he goes to sleep.

Autistic boy with toys laid out in a row at the side of his bed as he sleeps(c) 2003 by Nancy J Price (aka Mom) 

This young girl from Papua New Guinea has inherited albinism….

Albinistic girl showing a lack of pigmentation in her skin and hair sitting on mother's lap in Papua New Guinea

Sarah Rose is an Australian paralympic swimming competitor who inherited ‘achondroplasia’- a condition more commonly known as ‘dwarfism’.

Australian Paralympian Of TheYear ceremony 2012 Sarah Rose

Science projects

  • What traits have you inherited from your parents? You will find a more complete list of inherited traits at this Human Genetics article.
  • Research an inherited condition that is ‘disabling’ that you would like to learn more about.
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