Robert M. May 1992 The diversity of major taxonomic groups shown by the relative size of one representative, in Spektrum der Wissenschaft 12
John Kitses and Brooke Singer 2009 Our Chemically Modified Organisms
Marc Bellion c. 2010 History of life on earth, www.fauna-a-flora.lu
Anthony D. Barnosky et al. 2011 The earth’s sixth mass extinction, in Nature 471
Steve Jenkins 2013 One extant among one thousand extinct species, in The Animal Book
Proportion of endangered species in major taxonomic groups 2014, in International Union for Conservation of Nature and Natural Resources
Wilfried Westheide and Gunde Rieger 2013 Taxonomic order and organizational level of animal taxa, in Spezielle Zoologie, Teil 1
Georg Toepfer 2014 Richness of species and life forms in major taxonomic groups
Rodolfo Dirzo et al. 2014 Consequences of defaunation on ecosystem functioning and services from high (red) to low (blue) animal abundance, in Science 345
Anthony John Stuart 2015 Extant (green) and extinct (black) megafauna species in Subsaharan Africa, Northern Eurasia and North America, in Geological Journal 50
Wolfgang Haber 2016 Known and unknown diversity in major taxonomic groups, in Wie viel Wissenschaft braucht der Naturschutz
Yinon M. Bar-On, Rob Phillips and Ron Milo 2018 The biomass distribution on Earth, in PNAS 115