Convincing evidence to consider it an extinct species is currently lacking.
“Extraordinary claims require extraordinary evidence”, said Carl Sagan in the television program Cosmos. This statement came to mind when I read several news articles with bold titles, such as “4,600-Year-Old Egyptian Painting Depicts Extinct Species of Goose” and “Ancient art reveals extinct goose.” These headlines refer to a recent study on the Meidum Geese, a 4,600-year-old Egyptian painting that historians described as “one of the great masterpieces of the Egyptian animal genre”. It depicts several goose species, including two Red-breased Geese (Branta ruficollis). However, a closer look at these colorful paintings reveals some striking differences with this well-known species. Could the Meidum Geese represent an extinct taxon?
To answer this question, Anthony Romilio applied the Tobias criteria to the artwork. This method scores the characters between closely related taxa on a scale of dissimilarity. Low scores indicate that the taxa are very similar and could be classified as a single taxon (e.g., subspecies ), while high scores point to many dissimilarities and possibly distinct species. The first goose on the artwork showed low scores when compared to Greylag Goose (Anser anser) or Bean Goose (Anser fabalis), while the second painted goose most likely corresponds to a Greater White-fronted Goose (Anser albifrons). The third species of the Meidum Geese, however, did not accurately reflect Red-breasted Goose. Romilio writes that “This raises the possibility that the ‘Medium Geese 3′ may illustrate a distinct, yet now extinct goose population as has been suggested previously.”
Stating that there was an extinct goose species in ancient Egypt based on a painting is quite an extraordinary claim. In contrast to the news headlines, the paper provides a very balanced analysis of this claim. And although it is a possibility, I would argue that the extraordinary evidence to back this claim is currently missing. I am not convinced for two main reasons:
- Unique Artwork. The Meidum Geese are the only depiction of a Red-breased Goose in Egyptian art (to my knowledge). This suggests that they might have been seen as rare vagrants, and were later painted from the artists’ memory which can explain the differences. Moreover, if the painting represented an extinct taxon, you could expect independent artwork depicting this colorful bird.
- Not Accurate Enough. In the paper, the author argues that other species are realistically painted and hence we can assume that the “Red-breasted Meidum Goose” is also realistic. First, this reasoning is contradicted by the analysis of Meidum Goose 1, which could be either a Greylag Goose or a Bean Goose. If the paintings were accurate, you should be able to tell the difference. And second, the other goose species on the artwork belong to the genus Anser, which is not known for its colorful members. These “grey geese” do not leave much room for artistic freedom, in contrast to the colorful patterns on the Red-breasted Goose.
Fossils and Genomes
What could convince me that the “Red-breasted Meidum Goose” does represent an extinct species? Another clue might come from the fossil record or genetic analyses. Recently, a goose skull was discovered on Crete that is similar to the Red-breasted Goose. A morphological analysis of this skull might reveal whether it belonged to an unknown species that is closely related to the Red-breasted Goose. In addition, researchers might be able to extract ancient DNA from the skull and perform a proper phylogenetic analysis.
The genomes of present-day goose species might also hold the key to this mystery. Genomic analyses have uncovered signatures of hybridization events with now extinct species in the genomes of extant species, a phenomenon known as ghost introgression. Given the high levels of hybridization in geese, the extinct Egyptian species might have interbred with the Red-breasted Goose or another goose species. If so, we might be able find genetic traces of these ancient hybridization events. And if we are lucky, the introgressed regions might provide some insights into the phenotype of this extinct species. I am aware that this is very speculative and wishful thinking. But it would certainly be extraordinary evidence!
A Hybrid Goose?
In a discussion on Twitter, someone proposed the possibility of a hybrid. Although I like this suggestion, I do not think it is likely. If it was a hybrid, there was clearly a Red-breasted Goose involved. And hybrids with this species tend to be “drab” and lose their bright red markings.
Romilio, A. (2021). Assessing ‘Meidum Geese’ species identification with the ‘Tobias criteria’, Journal of Archaeological Science: Reports 36:102834.