Daily Bulletin


News

  • Written by Darren Curnoe, Associate Professor and Chief Investigator, ARC Centre of Excellence for Australian Biodiversity and Heritage, University of New South Wales, UNSW

Curious Kids is a series for children. If you have a question you’d like an expert to answer, send it to curiouskids@theconversation.edu.au You might also like the podcast Imagine This, a co-production between ABC KIDS listen and The Conversation, based on Curious Kids.

Are humans going to evolve again? Thank you. – Temi Bisiriyu, age 10, London.

Thanks for a great question, Temi. This is something I get asked a lot.

The short answer is that humans are evolving right now and will continue to do so even if we don’t notice it. This might sound a bit far-fetched, so let me explain what I mean.

Read more: Curious Kids: Where did the first person come from?

The big changes

Biologists who study evolution do so by examining evidence on two scales. The first scale is what we call macroevolution (“macro” means big). These are the big changes we see in the fossil record. They happen over long periods like hundreds of thousands, millions, or even tens of millions of years.

Think, for example, about the evolution of flowering plants or the appearance of mammals, both of which happened before 150 million years ago.

Or a bit closer to home, think of the evolution of our own biological group, the two-footed apes or hominins about 8 million years ago. Or of our species, Homo sapiens, which appeared in Africa more than 300,000 years ago.

I think this is the kind of evolution you have in mind. Most people think that evolution can only really be seen on this macro scale. Big changes like the evolution of two-footed walking or large human brains are examples of macroevolution.

Curious Kids: are humans going to evolve again? Understanding our evolution can tell us a lot about the health challenges we face today. AAP/UNIVERSITY OF WOLLONGONG

The small changes

The other kind or evolution, which is not so obvious, happens on a very small scale. Scientists call it microevolution (“micro” means small).

These tiny changes have to do with genes and while they may not result in a new species forming, they can have big implications for the people involved.

One way this happens is completely at random, because of the way genes shuffle about when a new baby is made. Geneticists have found that with every new generation – say you and your friends – the makeup of your genes as a group will be a little bit different to your parents and their friends.

Geneticists call this “random genetic drift” and it can be very strong in small populations of people leading to rapid changes over short periods.

This process can explain why some problems like autoimmune disease, which were once rare, have become more common today. Multiple sclerosis and coeliac disease are examples of autoimmune diseases.

How we live and what we eat

Sometimes, the environment in which a group of people lives can led to changes in the gene pool of this community. And those changed genes can get passed on to the next generation.

A really powerful example is when people first began farming wheat, maize (corn) or rice many thousands of years ago. Because of that change, humans started to eat lot more starchy foods.

This led to some big physiological changes because some of these first farmers weren’t really able to digest large amounts of starch.

Over a short period of time — a couple of thousand years or even less — a gene that helped them digest starch (the amylase gene) became much more common in early farming communities.

Curious Kids: are humans going to evolve again? When humans started farming maize (corn), that influenced the way we evolved. Flickr/Pat Dalton..., CC BY

In fact, people alive today whose ancestors were growing starchy foods have many more copies of this gene in their DNA than people whose ancestors didn’t.

Another example involves the gene that produces an enzyme called lactase, which allows adults to digest milk and other dairy products. If your ancestors drank a lot of milk, chances are you inherited that gene. Other people may have dairy intolerance because their ancestors didn’t drink as much milk.

So, as you you can see human evolution hasn’t really stopped. And understanding our evolution can tell us a lot about the health challenges we face today.

It might even help us to understand where we could be headed as humans shift the climate globally, perhaps even changing the future course of our evolution.

Read more: Curious Kids: how do bushfires start?

Hello, curious kids! Have you got a question you’d like an expert to answer? Ask an adult to send your question to curiouskids@theconversation.edu.au

Curious Kids: are humans going to evolve again? CC BY-ND Please tell us your name, age and which city you live in. We won’t be able to answer every question but we will do our best.

Authors: Darren Curnoe, Associate Professor and Chief Investigator, ARC Centre of Excellence for Australian Biodiversity and Heritage, University of New South Wales, UNSW

Read more http://theconversation.com/curious-kids-are-humans-going-to-evolve-again-116990

Writers Wanted

The Role Of The Ego In Gambling

arrow_forward

Set ground rules and keep it intimate: 10 tips for hosting a COVID-safe wedding

arrow_forward

Why equal health access and outcomes should be a priority for Ardern's new government

arrow_forward

The Conversation
INTERWEBS DIGITAL AGENCY

Politics

Prime Minister Interview with Kieran Gilbert, Sky News

KIERAN GILBERT: Kieran Gilbert here with you and the Prime Minister joins me. Prime Minister, thanks so much for your time.  PRIME MINISTER: G'day Kieran.  GILBERT: An assumption a vaccine is ...

Daily Bulletin - avatar Daily Bulletin

Did BLM Really Change the US Police Work?

The Black Lives Matter (BLM) movement has proven that the power of the state rests in the hands of the people it governs. Following the death of 46-year-old black American George Floyd in a case of ...

a Guest Writer - avatar a Guest Writer

Scott Morrison: the right man at the right time

Australia is not at war with another nation or ideology in August 2020 but the nation is in conflict. There are serious threats from China and there are many challenges flowing from the pandemic tha...

Greg Rogers - avatar Greg Rogers

Business News

Luke Lazarus Helps Turns Startups into Global Stalwarts

There are many positive aspects to globalization. It is no secret that those who have been impacted by globalization tend to enjoy a higher standard of living in general. One factor that has led to ...

Emma Davidson - avatar Emma Davidson

Digital-based strategies that grow and expand your business

Small and medium-sized businesses are increasingly relying on new technology solutions to strengthen their product development, marketing, and customer engagement activities. Technology adoption...

News Co - avatar News Co

What Few People Know About Painters

What do you look for when renting a house? Most potential tenants look for the general appearance of a house. If the house is poorly decorated, they are likely to turn you off. A painter Adelaide ...

News Co - avatar News Co



News Co Media Group

Content & Technology Connecting Global Audiences

More Information - Less Opinion