Why So Many Species?

Why So Many Species?

Only in the last year have ecologists determined a reliable count of the total number of species on Earth. For eukaryotic species—organisms with a membrane-bound nucleus—the estimate is 8.7±1.3 million (6.5 million land species and 2.2 million marine species).1 Estimates of the number of prokaryotes (bacteria and archaea), species whose cells lack a nucleus, range from 0.1 to 10.0 million.2

Now a team of six astrobiologists proposes a set of experiments to address the question, why are there so many species on Earth?3 This question, the team notes, is “central to evolutionary biology.”4 More than that, it is crucial to the creation-evolution debate. Can natural processes alone explain such a high number of species, or must God’s supernatural intervention be included?

For the location of these experiments the team chose Cuatro Ciénegas Basin (CCB), a desert oasis in Coahuila, Mexico. From a naturalistic perspective, speciation events should occur at the highest rates and greatest efficiencies possible at this unique site. The team observed that CCB’s species diversification and low phosphorus availability, in combination with “mechanisms for nutrient recycling and community cohesion result in enhanced speciation through reproductive as well as geographic isolation.”5 Next the team selected a set of microbial species they knew, from other studies, manifest the highest probabilities for speciation events. These selected species were ones that demonstrated the highest rates of horizontal gene transfer, the greatest food and nutrient plasticity, and the highest capabilities for geographic travel.

The team recommends that experimental ecology research groups perform long-term evolution experiments at CCB where different groups would “experimentally manipulate nutrient availability in microbial communities” and “monitor how microbial diversity responds to shifts in nutrients.”6 The goal would be to measure how many new species appear per unit of time and how dramatically new species differ from old ones.

Naturalistic models require that speciation rates be high enough and generate changes dramatic enough to account for the evolution of over 9 million species from the purported common ancestor of all life, as well as replace the species that go extinct naturalistically. Sufficiently dramatic changes mean some demonstrated capability for the microbes to naturally and quickly become complex multicellular, multi-differentiated organisms and for the microbes not to revert back to their original forms once the environmental pressures inducing the “evolution” are removed.

Given the proposed artificial evolutionary inducements, if the speciation rate and kind at CCB falls short, then the naturalistic models will have been falsified. We at Reasons To Believe predict that presentday long-term evolution experiments will reveal results falling far short of the change rates and kinds in Earth’s life documented in the fossil record. Such a biblical perspective recognizes that we are currently in God’s seventh day wherein He is resting from creation activity.

  1. Camilo Mora et al., “How Many Species Are There on Earth and in the Ocean?” PLoS Biology (August 23, 2011): doi:10.1371/journal. pbio.1001127.
  2. P. M. Hammond, in Microbial Diversity and Ecosystem Function, eds. D. Allsopp, R. R. Colwell, and D. L. Hawksworth (Wallingford, Oxon, U.K.: CAB International, 1995), 29–71.
  3. Valeria Souza et al., “Travel, Sex, and Food: What’s Speciation Got to Do with It?” Astrobiology 12 (July 2012): 634–40.
  4. Ibid., 634.
  5. Ibid.
  6. Ibid., 638.