ACADEMIA Letters A Hopeful Monster? Steve Anderson Some years ago (ok, in 1970 if you want to guess my approximate dotage) I was in Chicago at the Field Museum of Natural History to identify and examine an assembly of reptiles collected by the Street Expedition to Iran. I picked up a glass jar containing what appeared to be a specimen of a Persian false-horned viper (Pseudocerastes persicus). I removed it from the container. To my amazement, it had what appeared to be some sort of arachnid, perhaps a solpugid, clinging to the tip of its tail. How unlikely! Upon closer inspection it proved to be an anatomical part of the snake itself, a terminal bulbous swelling and elongated scales, all serving to give the appearance of some spider-like caudal appendage. The term “hopeful monster” crossed my mind unbidden; unbidden, as I have never given credence to this notion. This term was created by the German geneticist Richard Goldschmidt to label his belief that species were formed by the sudden appearance of macromutations, giving rise to entirely new forms of animals with unexpected morphologies. The vast majority would be nonadaptive, he reckoned, but just occasionally one would find a niche within the grand scheme of life. It wasn’t that he completely dismissed Darwinian natural selection, but for him it constituted a sort of fine tuning of his successful monsters. Most evolutionary biologists dismissed this fanciful origin of species from its first publication. I won’t here go into the notion that small mutations may produce regulatory changes that produce significant evolutionary effects as promoted by the late paleobiologist Stephen J. Gould. You could Google it, as they say. To return to the snake specimen under discussion, its caudal appendage remained an unsolved enigma, perhaps a mutation, possibly a tumor, maybe a developmental defect triggered by an injury. The precise locality of its collection wasn’t even known. It had been “collected” by villagers with the aid of a large rock that had crushed the head. It did not seem worth publishing under the circumstances, but over the years it occasionally rose to mind. Academia Letters, December 2021 ©2021 by the author — Open Access — Distributed under CC BY 4.0 Corresponding Author: Steve Anderson, asaccus@aol.com Citation: Anderson, S. (2021). A Hopeful Monster? Academia Letters, Article 4441. https://doi.org/10.20935/AL4441. 1 In about 2005, Dr. Papenfuss of the Museum of Vertebrate Zoology, University of California, Berkeley was visiting Iran and was shown a second specimen of the viper with the weird tail. It had been collected by an Iranian amateur naturalist, Hamid Bostanchi. The preservation was poor, and the specimen had deteriorated, exposing a small passerine bird in the stomach; a glimmer of explanation of the use of the strange tail might be seen. A speculation: the peculiar tail served as a caudal lure. Vipers and a few other snakes are sit-and-wait, ambush predators. They curl up under shrubs or beneath loose sand, sometimes with a tail tip exposed, awaiting their victims to come along. Some of these species have the end of the tail a distinctly different color from the body. By wriggling the tail, they attract a small rodent or lizard to approach within striking distance. It has been proposed that the rattle at the end of a rattlesnake’s tail began as a caudal lure, eventually becoming a startle/warning devise as a secondary adaptation. I have seen them slowly moving the rattle quite soundlessly on occasion. Our viper’s tail is specifically attractive to birds. As the tail tip is moved across the ground, its appearance and movement are uncannily like those of a small spider. Several videos of this phenomenon can be seen on YouTube. In any case, I surmised that the monster’s hope had been realized and I wrote up a formal description of the snake and, along with Mr. Bostanchi and Dr. Papenfuss, published it. Our snake is now known formally as Pseudocerastes urarachnoides, the Greek meaning “falsehorn, spiderlike tail.” Subsequently, it has been found in several locations along the western slope of the Zagros Mountains in Iran and eastern Iraq. On my most recent trip to Iran in 2015, I was privileged to see three of these snakes in the field at one location and to photograph one of them. They live in an area of limestone cliffs and gypsum formations and seek refuge in cracks and crevices where moisture and coolness are available during warm months of summer. Their body scales are rough in appearance and provide good camouflage in their rocky habitat. During the cooler hours of morning and evening, they emerge to lie in ambush under bushes. They position the tail-tip close to their head so that an attacking bird is in position for an instant venomous strike. Diurnal activity begins in April and continues through November, peaking during spring and autumn. Mating reportedly is nocturnal in this egg-laying species. Academia Letters, December 2021 ©2021 by the author — Open Access — Distributed under CC BY 4.0 Corresponding Author: Steve Anderson, asaccus@aol.com Citation: Anderson, S. (2021). A Hopeful Monster? Academia Letters, Article 4441. https://doi.org/10.20935/AL4441. 2 O. Mozaffari photo Academia Letters, December 2021 ©2021 by the author — Open Access — Distributed under CC BY 4.0 Corresponding Author: Steve Anderson, asaccus@aol.com Citation: Anderson, S. (2021). A Hopeful Monster? Academia Letters, Article 4441. https://doi.org/10.20935/AL4441. 3 S. C. Anderson photo And what is to become of this narrowly endemic species as the climate changes? There have been attempts to model changes in habitat under possible climate regimes. Most of these speculations center on temperature and precipitation, but the fundamental niche depends on more than local climate. In the case of the spider-tailed viper, continued survival may depend Academia Letters, December 2021 ©2021 by the author — Open Access — Distributed under CC BY 4.0 Corresponding Author: Steve Anderson, asaccus@aol.com Citation: Anderson, S. (2021). A Hopeful Monster? Academia Letters, Article 4441. https://doi.org/10.20935/AL4441. 4 upon changes in bird availability as migration and nesting are affected by climatic events. Of more immediate concern for this narrowly distributed rare snake is its appeal to live animal fanciers. Although these vipers are officially protected in Iran, there are many experienced professional snake collectors who can easily poach them. I have seen a photograph showing several of these snakes in captivity in Germany. This sort of over-collecting can quickly threaten the existence of the small populations of this reptile. The Iran Department of Environment has proposed the listing of this species in CITES Appendix II. Although this action would protect against acquisition by public institutions, such as zoos and museums, it would do little to prevent illegal poaching for the pet trade. Academia Letters, December 2021 ©2021 by the author — Open Access — Distributed under CC BY 4.0 Corresponding Author: Steve Anderson, asaccus@aol.com Citation: Anderson, S. (2021). A Hopeful Monster? Academia Letters, Article 4441. https://doi.org/10.20935/AL4441. 5 References Bostanchi, H., S. C. Anderson, H. G. Kami, and T. J. Papenfuss. 2006. A New Species of Pseudocerastes with Elaborate Tail Ornamentation from Western Iran (Squamata: Viperidae). PCAS, ser. 4, vol. 57, No. 14, pp. 443–450. Academia Letters, December 2021 ©2021 by the author — Open Access — Distributed under CC BY 4.0 Corresponding Author: Steve Anderson, asaccus@aol.com Citation: Anderson, S. (2021). A Hopeful Monster? Academia Letters, Article 4441. https://doi.org/10.20935/AL4441. 6