The impact of humans on Earth

In this page, we introduce some numbers and estimates of the impact of humans of planet Earth. Since the dawn of civilization, humanity has caused the loss of 83% of all wild mammals and half of plants, while livestock kept by humans abounds.


Institutional partner

Juanma Garcia
General support

Juanma Garcia


Content development

CRI logo

CRI Paris

Funding for prototyping

Do it at home: shopping list

This is an example of the materials we can buy online in France to make in total 50 tests. We typically make groups of 3-5 students working together and dividing tasks, so the list below (120 euros) serves for 70-90 students. I am sure you will be able to also find the same products elsewhere, so you do not need to follow exactly this link to buy the product.

  1. Test NH₄ d'Eau Douce/du Mer pour Aquariophilie 50 tests (Link) / 14.2 euros
  2. Test NO₃ d'Eau Douce/du Mer pour Aquariophilie 50 tests (Link) 17.95 euros
  3. Test PO₄ d'Eau Douce/du Mer pour Aquariophilie 50 tests (Link) 10.31 euros
  4. Test Cu/Cuivre d'eau pour Aquariophilie 50 tests (Link) 14.51 euros
  5. Tests Liquides - Test-Set Fer 50 tests (Link) 14.24 euros
  6. 5 kg 5000 g de charbon actif externe pour aquarium (Link) 26.99 euros
  7. Lot de 100 bandes d'essai pH neuf (Link) 19.45 euros
  8. Bouteilles en plastique Octopus 10 x 500 ml (Link) 12.95 euros


Water watchers was started by Sonia Aguera and Juanma Garcia in 2018 as a collaboration with the Eramus+ project SWIS.


Thanks to the teacher Rosa Belmonte, coordinator of the Eramus+ project SWIS (science work in schools, link here) in the High School IES Antonio Dominguez Ortiz, and Maria Jose Leon from the public laboratory of the city of Sevilla.


Rosa is a very dedicated teacher that invited us to her high school and gave us useful feedback in the content we prepared. Maria Jose is a scientist in the city lab of Sevilla and very active in science communication and education.