Dr. Ralf Britz is a leading ichthyologist and taxonomist, and Head of the Ichthyology Section at Senckenberg World of Biodiversity. He has been involved in a total of 73 species descriptions and has been a key team member in the discovery of seven species which needed the creation of new genera. He was also the lead author on two papers describing the Gollum snakehead Aenigmachanna gollum: a new species in a new genus in an entirely new family.
With Shoal’s release of a landmark New Species 2021 report tomorrow, we caught up with Ralf to get the low-down on what discovering and describing new species really means.
What does it mean to describe a species, and how is it done?
When you describe a new species scientifically this process is often referred to among the public as having identified a new species. The process starts with the impression that you have found a species that does not have a scientific name, i.e. it is unknown scientifically. You then need to compare your specimens of what you think may be a new species with specimens of similar species that already have a name.
As taxonomy is one of the oldest scientific biological disciplines, this can be quite a cumbersome process, because you have to deal with all the species descriptions since and including Linnaeus’ 10th edition of his Systema naturae, published in 1758 and the starting point of animal taxonomy. If you are lucky and the group you work on has only a few species, then it is easy to compare your material with already collected material of the other species. This usually involves comparison with what we call type specimens, the specimens used to describe species. One of these type specimens is chosen as the holotype, the actual name bearer, the one specimen that is permanently linked to that name. These are stored ideally in publicly accessible museum collections. If, after comparison, you find that the specimens of what you thought were a new species are identical to one of the already described ones, then that is the end of the story. But if you find consistent and significant differences to all the known species in the group you are studying then you have probably found a new species.
The next step is then to write up a scientific manuscript in which you detail how your new species differs from already described (named) species, and you propose a name for it. The name may refer to a characteristic feature of the new species, or the place where it was collected, or it may honour a person, such as the person who collected it, an influential colleague or someone who supported your work.
In most cases the new name concerns just the new species. But sometimes you find an organism that you cannot easily fit into a larger group of similar and closely related species, a group we call a genus. In this case you may need to create a new genus for this new species. Here, the same rules apply you need to check all genera (plural of genus) in the larger group of organisms (a group we call a family). If you find you cannot fit it into one of the known genera, you can describe a new genus.
Once you have written up your findings relating to a new species or new genus, you submit your manuscript to a scientific journal for peer review. This means the manuscript is sent to other experts in the field who read your manuscript and point out potential problems, errors, mistakes etc. They provide the quality check before a manuscript is accepted and then published. They may ask you to revise your manuscript, check sources you may have overlooked, ask for additional details, or if you have made some major mistakes, suggest to reject your manuscript. If you have done your job, though, it may need no or just minor revision and will then get accepted for publication. Once it is published by a scientific journal and you have made sure you followed all the necessary steps that are required by the Code of Zoological Nomenclature – a set of rules that determine what has to be done for a name to be published in a valid way – then the new species is officially described and carries the name you have chosen.
I want to briefly touch on a worrying aspect of species descriptions that has started to plague taxonomy: the unholy alliance between self-proclaimed taxonomists and journals that will publish anything of any quality if you pay for it, the so-called predatory journals. There is an increasing number of manuscripts getting published which did not go through the strict and necessary step of peer review. Publication of these poor-quality species descriptions is a problem, because you cannot just ignore them as in other areas of science where poor papers just disappear in the garbage dump of scientific publications. Even poor-quality papers that describe new species will need to be considered due to the specific rules of nomenclature that need to be applied. Showing that these manuscripts are poor quality, and that the so-called new species is actually not new often involves so much more work, effort, time and money from you than the person invested who wrote the poor-quality manuscript. I know of cases in which one person described more than 20 new species from a well-known area of the world, all in predatory journals and with not a single of these so called new species really being new. Imagine that for each of these 20 or so new species you need to demonstrate that the original paper describing them is of poor quality and that these are not new species. This means you waste precious time, in which you could have described 20 new species with the level of quality that is necessary and is guaranteed by a proper peer review. Such taxonomic vandalism, as it has been termed, hampers the discovery of new species in a time when diversity is disappearing at an alarming rate.