Appendices 3-5 in The Killing Age (pp. 553-67) contains detailed information wild animal deaths, climate change, and the explosive economic growth in Britain and the United States. We revisit some of this information here, in an interactive form.

Readers wanting to know more about animals might want to explore the following links:

1. Wild mammals: https://ourworldindata.org/wild-mammal-decline 

2. Species threated by extinction: https://ourworldindata.org/grapher/number-species-threatened

3. Monitored wildlife populations since 1970: https://ourworldindata.org/grapher/global-living-planet-index

4. Elephants: https://ourworldindata.org/elephant-populations

5. Whales and whaling: https://whalinghistory.org/whaling-history-website-live/

There have been enormous developments in our understanding of climate and other planetary systems, though recent cutbacks in research funding by the American government threaten these advances. I especially relied on the article by Abram et al in Nature, vol. 536, 25 August 2016. By accessing the online version of the article, https://www.nature.com/articles/nature19082, you can also access their various datasets. There are multiple organizations where interested readers can access up-to-date information:

1. https://berkeleyearth.org/data/, where you can access a wealth of information. One important visualization of temperature change is their https://berkeleyearth.org/dv/global-temperature-anomaly-from-1850-2022/

2. https://ourworldindata.org/climate-change

NOAA and NASA were historically important sources of information on climate, for example: https://www.ncei.noaa.gov/access/monitoring/climate-at-a-glance/global/time-series. Because of the uncertain status of these US government agencies regarding global warming, it is unclear if the information will continue being publicly available.

Data on GDP is relatively easily available. To begin with, go to: https://ourworldindata.org/. Another exceptionally rich source is the Maddison Project Database, easily accessible at https://www.rug.nl/ggdc/historicaldevelopment/maddison/releases/maddison-project-database-2020?lang=en.