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One Planet

Are Humans Good for the Planet?

Subject Area
Sustainability
Estimated Classroom time
50 minutes
Difficulty
2 of 3 — Moderate

Humans have been on Earth for a tiny fraction of its history. So why has everything changed so fast, and can we change it back?

Main Theme: Humans are both the cause and the solution. The Great Acceleration shows how quickly human choices cause damage, but targeted recovery can happen just as fast, which lets learners see themselves as agents of change rather than bystanders.

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Session objectives

  • Describe how quickly human impact on the planet has accelerated, using evidence from the Great Acceleration.
  • Explain how biomagnification led to the decline of species such as the peregrine falcon, from a chemical sprayed on a field to a bird that never touched a crop.
  • Explain why recovery is possible and how quickly it can happen, using the peregrine falcon and the humpback whale.
  • Outline the three steps of conservation (Stop, Protect, Restore) and apply them to a threatened species.
  • Evaluate which of the three steps is hardest to achieve, and justify a view on whether humans are good for the planet.

Misconceptions to watch for

  • The damage is too far gone to reverse.

    The peregrine falcon and the humpback whale were both pushed to the brink, and both have recovered within a few decades. It took action to get there, and it worked. Not every species gets that chance, but these two show it can be done.

  • Conservation is for governments and scientists, not people like us.

    Policy and science matter, but ordinary people have played real parts too. Public pressure, the things people choose to buy, and communities keeping watch on local wildlife have all helped conservation succeed.

If a student asks…

Is the illegal wildlife trade really as big a problem as climate change?
They're different problems, and it isn't a contest. But the illegal wildlife trade is serious in its own right. It's estimated at up to around 23 billion dollars a year, and it pushes species towards extinction and throws the ecosystems they belong to out of balance.

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Teacher Tips

Hook

  • It helps to keep the ordering quick. It's a warm-up, not the lesson, and most pairs will get it roughly right. The payoff is the compression: ask which two images sit closest together in time. Learners consistently place the plastic bottle far earlier than it belongs, which is the first hint that the story is about the last eighty years and not the last five thousand.
  • "Have these changes all made life better?" is a key question. You might find learners give a performed answer, that inventions ruined the planet, because they can guess the sustainability slant of the lesson. It helps to push back by asking which of the six they would give up. Flight, medicine and electricity are not easy to surrender, and the discomfort is the point.
  • One image is not like the others. The wind turbine or electric car is the only thing on the board invented to undo the effects of the rest. Asking which one doesn't belong, and why, plants the Stop, Protect, Restore idea twenty minutes before you name it.

ITZA Pathways

  • Pathway 1 is bleak by design, and some learners will arrive at "we are doomed" before the lesson has offered them anything else. It helps not to argue with it. You might tell them Pathway 2 is the answer to exactly that objection, and that they can judge for themselves when they get there.
  • Biomagnification is the mechanism the whole session rests on, and it's easily reduced to "DDT killed the falcons". You could ask "How does a chemical sprayed on a field end up in a bird that never touched a crop?" A learner who can trace the chain can use the peregrine as evidence later.
  • The detail worth looking out for in Pathway 2 is the timescale. The peregrine came back within a single human lifetime, which is what turns the recovery from a nice anecdote into an argument about what is still possible.

Classroom Activity

  • It helps to work the orangutan example against all three steps aloud before groups start. Without it, most groups write three versions of the same sentence about logging. The steps are three different kinds of action: remove the cause, make it illegal, and actively rebuild.
  • Protect is where thinking tends to collapse. Learners write "ban it" and consider the job done. You might ask "Who would enforce the ban?" and "What happens when the country the species lives in can't afford to?" That's where the Modern Studies and ethics links in this session actually live.
  • Restore often attracts the fantasy answers, usually cloning or a very large zoo. You could steer towards corridors, replanting, breeding and release, then ask "How long would your plan take?" The honest answer is decades, which is the realism check the peregrine case study has already given them.

Plenary

  • Part 2 asks which step is hardest. Most will say Restore because it sounds like the biggest job. The stronger answer is usually Stop, because it's the only step that requires somebody to give something up. Either position is fine if they can argue it, and the disagreement is more useful than consensus.
  • The lock-in is from Barack Obama, former US president. A sharp learner may object that "the last generation that can do something" is rhetorically convenient rather than literally true. It's a fair challenge and worth allowing, since the session has just spent twenty minutes arguing that recovery is possible.
Learner journal tip

If using the editable journal, it helps to have each learner make their own copy at the start of the course and save it somewhere easy to find again. Perhaps in a folder on their laptop or in their school drive. It carries across every session, so if the plenary runs short, they can finish Part 2 or the later sections at home without losing earlier reflections.

Extensions

Curriculum links

Science & Biology
Ecosystems, food chains, biomagnification, biodiversity loss, trophic cascades, keystone species and conservation biology.
Geography
Human impact on the natural environment, land use change, global population growth, environmental indicators and physical systems.
Modern Studies
Global interdependence, international law and cooperation, governance of natural resources and environmental policy.
Health & Wellbeing
Citizenship and environmental responsibility, values and ethical decision-making, and understanding global issues that affect communities.
RME & Ethics
Moral responsibility towards the natural world, evaluating competing human interests, and the ethics of economic growth against ecological preservation.