What is your email?Don't miss out on any great stories.Receive the Very Interesting Newsletter.All the news about the coronavirus in your email.Receive the Very Interesting Newsletter.Thank you for subscribing to our Newsletter.Many species of animals and plants exhibit mimicry;these desert plants do so by resembling the stones that surround them.In nature, instances of mimicry abound.Mimicry is the ability to acquire the appearance of other living beings or elements of the environment, obtaining certain advantages, generally deceiving the senses of animals.The most common cases of mimicry are found in animal species: insects that look like branches to avoid being hunted;flies that look like wasps to scare away their predators;praying mantises that look like orchids to avoid being seen... Some forms of mimicry are more subtle, and do not involve the organ of sight;Such is the case of some insects that parasitize anthills, imitating the smell of ants so as not to be detected.Although it might seem that the most iconic example of mimicry is that of the chameleon and its particular ability to change color;in reality, his case is not so much a mimicry, but rather a form of communication.It would be mimetic, however, the change in color and texture that some octopuses experience.Also among plants there are cases of mimicry.Orchids that look like bees to facilitate their pollination, flowers like Rafflesia that emit the smell of rotting meat to attract insects that feed on carrion, or the case of plants of the Lithops genus, that look like stones.In fact, its common name is stone plant.The plants of the Lithops genus are typical of desert environments, specifically in southern Africa.They are species very well adapted to survival in conditions of extreme drought;that is, they are xerophytic species.Each plant is made up of one or more subunits, called corpuscles, which in turn are made up of two leaves, arranged symmetrically, that protect the meristem, the area where the corpuscle grows.Every so often, the corpuscle forms two new sheets, and the previous ones are reabsorbed.The leaves are extraordinarily fleshy, filled with water, rounded and with a flattened upper surface.They are usually adorned with colors and more or less complex line patterns, which contribute to the general camouflage, through a cryptic and disruptive effect.According to the scientific database The World Flora Online, the genus Lithops has 39 accepted species, but differentiating one from another is very difficult.On the one hand, populations of the same species can have very different aspects, depending on the environment in which they develop;when a species has this high variability, it is said to be polymorphic.And on the other hand, different species can look very similar, if they develop in similar environments.Polymorphism can happen for different reasons.In some cases, it responds to a genetic variability of the populations that, in the long term, can give rise to a process of speciation, if the genetic isolation is sufficient.When this circumstance occurs, a seed of a specific morphological type —what is called a 'morphotype'— will give rise to a plant of the same morphotype, even if it is planted in a place where the dominant morphotype is another.But in other cases, the organisms simply have a high flexibility, and the polymorphism responds to a process of mere acclimatization to the environment.When this type of polymorphism occurs, a seed obtained from a species with a certain morphotype can give rise to a plant with a different morphotype, which will depend on the environment.In stone plants we find both processes.On the one hand, there are different genetic populations within each species, which adjust to the different morphological populations observed.However, this explanation of variability as a by-product of natural genetic variation is insufficient to explain the morphotypes of the genus Lithops.It has even been observed that the same plant can have corpuscles with leaves with different patterns, or even more fascinating, that the same corpuscle, when renewing its leaves, changes its pattern with respect to the previous leaves.The origin of these polymorphisms is ultimately evolutionary, and has been shaped by the selective pressures induced by the visual ability of their predators.Many plants of the genus Lithops have varieties for ornamental cultivation, particularly appreciated by fans of cactus cultivation.They form an attractive background, compatible with many other xerophytes.These crop varieties, in principle, are not at risk of disappearing.But its natural environment is not without risk.Paleoclimatic studies show that since the last glacial maximum, about 20,000 years ago, the distribution area inhabited by the different species of the genus Lithops has been significantly reduced and, as a consequence, also their distribution.In addition, a recent study by the International Organization for the Study of Succulent Plants (IOS), published in the specialized journal Bradleya, shows that climate predictions, based on observations of anthropogenic global change, suggest an even greater reduction in the area of availability of the genus, and the possible extinction of two species as their habitats become unsuitable.Crook, I. et al.2022. Environmental barriers to the distribution of the genus Lithops: present, past and future.Bradleya, 2022(sp40).DOI: 10.25223/brad.sp40.2022.a5Loots, S. et al.2019. Genetic variation among and within Lithops species in Namibia.Plant Systematics and Evolution, 305(10), 985-999.DOI: 10.1007/s00606-019-01619-wStancher, G. 2017. Hypothesis on evolutionary origin and adaptive value of polymorphism in Lithops NEBr.Bradleya, 2017(35), 113-121.DOI: 10.25223/brad.n35.2017.a10WFO.2021. Lithops NEBr.(wfo-4000021986).The World Flora Online.I'm a doctor in biology, specializing in invasive species.I try to spread science and nature while fighting hard against pseudoscience and magical thinking.When I have time, I hunt pokémon and do crafts.Also, I'm (a little) addicted to twitter.Don't miss out on any great stories.Receive the Very Interesting Newsletter.All the news about the coronavirus in your email.Receive the Very Interesting Newsletter.Thank you for subscribing to our Newsletter.