How different ecological environments affected the evolution of snakes

Introduction

Snakes are long legless reptiles that play a vital role in the natural environment as well as food webs. They have a high-developed sense of sight, taste, touch, hearing, and can track their prey with great accuracy. Some snakes have lethal venom that paralyzes and kills their prey while others have muscular bodies for squeezing their prey to death. Several types of snakes exist in different parts of the world, from small ones to giant serpents, some living in water (Seigel et al. 453). Some people fear snakes terribly, yet there are some that are harmless since they have no venom. In the story "Sweat" by Zola Neale Hurston, published in 1926, Delia is terrified of a snake that her husband brings to the house, which finally bites him (Hurston). The ecological conditions have affected the nature of snakes, leading to adaptation tactics that enable them to survive the changing environments. Therefore, snakes are exceptionally diverse, leading to a great deal of evolutionary change.

Anatomical and Phylogenetic Research

According to anatomical and phylogenetic research, snakes evolved from lizards as terrestrial vertebrates (Caprette 469). The lizards and snakes are highly sensitive to changes in temperatures resulting from factors that include climate change because of their exothermic nature. This condition requires snakes to depend on ambient environmental temperatures for maintaining vital physiological processes. Snakes have a very close relation to lizards and the changes in the environmental conditions have led to the evolution of snakes in different parts of the world. There are more than 3400 species of snakes occupying different environments such as terrestrial, aquatic, arboreal, and fossorial (Willson and Dorcas 2). Growth as well as natural selection has led to morphological head differences related to snakes and lizards. The variation in cranial structures is closely linked to ecological habitats and diet choices in snakes. The manner in which snakes evolved and diversified was not a simple process but involved the combination of survival for the fittest and development process. This created more underground lifestyles followed by colonization of several habitats that include water, forests, deserts, and prairies.

Evolutionary Convergence and Divergence

Evolutionary convergence and divergence have affected the characteristics of snakes depending on the areas they live in. Convergence occurs over time and constitutes widespread patterns that occur whenever separate species independently go through evolution with similar phenotypes to respond to similar ecological conditions. Convergence in pairs of species is frequently used as proof of adaptations through natural selection. For instance, the morphology of the snake's skull is affected by habitat specialization since there is a potential relationship between skull shapes and habitat preferences. The cranial shape difference in various ecological niches determines the difference between the fossorial ecological niche and every habitat's modes (Willson and Dorcas 3). Natural selection influenced the sizes and shapes of evolution in smaller, encased, and non-flexible head-skulls that were adaptable to fossorial environments. Ancestral state's reconstruction shows that the ancestors of crown serpents were night hunters that foraged and hunted their prey. The serpents consumed soft-bodied vertebrates and invertebrate creatures that lived in similar environments. They lived in terrestrial places in regions that were well-watered and vegetated. An example of a snake originated on land in the mid-Early Cretaceous after which the crown-group followed after twenty million years, in the Albian era (Hsiang et al 3). The snakes inhabited places with vegetation as well as in warm, moist, and equable climates.

Venomous Snakes and Geographic Variation

Venomous snakes differ depending on the ecological location of the reptile. For instance, venom from the eastern diamondback rattlesnakes that live in Everglades is different from the toxins from a similar species living in the Florida panhandle. However, in the Southeastern US, the venom of the eastern coral serpent does not change (Caprette 471). Thus, the geographical location of the snake tends to alter some characteristics as well as venom differences in two kinds of snake species. Every venomous snake type can produce specific venom, containing almost fifty to two hundred toxic protein content and fragments, which change with the type of prey of the serpent (Lillywhite 317). The small reptile animals consumed by the eastern coral serpent as well as the rodents eaten by the rattlesnake species will determine the amount of venom released. Therefore, evolutionary attacks and counterattacks the existing genetic variations, which increase venom resistance that spreads in the prey populations, affecting the snake venom recipe that helps in restoring its effectiveness. Local co-adaptations that connect the predator and prey and considerable region diversification of the variant and amount of the varying venomous protein are important. The amount of proteins found in coral snake venom in different parts of the state could not be distinguished from the country as the coral snakes release venom consisting of varying components of poisonous proteins in almost each sub-population of the snake. For instance, two venom types, in which one is capable of paralyzing preys, can be traced in huge quantities in the northern population of serpents, but are not found in the snakes belonging to Caladesi Island in Tampa (Lillywhite 317). Ecological distributions, therefore, facilitate the existence of variations in snakes of the same species. The case can be a reflection of the differences in co-evolutional developments in the species and the typical reptiles that are considered as preys.

Snake Skin Color Patterns

Snakes are known to have a wide diversity of skin color patterns. The arrangement of body colors is associated with behavior, especially the tendency to run away from enemies. Snakes containing plain or longitudinal stripes must get away from their enemies through camouflaging. Plain serpents are known to hunt aggressively since their patterns enable them to inform the prey about movement. Blotched snakes apply the tactic of ambush-based strategies since it facilitates blending into environments containing irregular objects such as sticks, rocks, or leaves (Sheehy et al 245). Serpents live in various climates that include arid deserts and open oceans. Thus, the ecological and evolutionary development of snakes requires extensive research. Furthermore, the evolution and development of their limbs as well as axial skeleton suggests that there is a relationship between limb loss and body elongation for serpents. The studies that assessed the early ecological and evolutionary origin of serpents dealt with discrete morphological variations.

Conclusion

Snakes are fascinating animals to some people and scientists, although some individuals are scared of them, just like Delia in the short story, Sweat. Some studies on snake ecology and origins have been done to promote understanding of snake species. However, there is a need for more comprehensive research on the ecology, such as population biology. The gaps in this area limit human ability to develop effective conservation and management strategies for conservation efforts. The study of snakes and ecology avails various opportunities for ecological knowledge related to other taxa. The shapes, as well as the number of scales on various body parts such as the head, back, and belly, can be utilized for taxonomic purposes. Therefore, more studies on the ecological evolution of snakes can offer extra ideas about the existence of different types of snakes in the universe.

Works Cited

Caprette, Christopher L., et al. “The Origin of Snakes (Serpentes) as Seen through Eye Anatomy.” Biological Journal of the Linnean Society, vol. 81, no. 4, Apr. 2004, pp. 469–482. EBSCOhost, doi:10.1111/j.1095-8312.2003.00305.x.

Hsiang, Allison Y., et al. “The Origin of Snakes: Revealing the Ecology, Behavior, and Evolutionary History of Early Snakes Using Genomics, Phenomics, and the Fossil Record.” BMC Evolutionary Biology, vol. 15, no. 1, July 2015, pp. 1–22. EBSCOhost, doi:10.1186/s12862-015-0358-5.

Hurston, Zora Neale. Sweat. Rutgers University Press, 1997.

Lillywhite, Harvey B. “Snakes: Ecology and Conservation.” BioScience, vol. 60, no. 4, Apr. 2010, pp. 315–317. EBSCOhost, doi:10.1525/bio.2010.60.4.11.

Seigel, Richard A., et al. “Ecology of an Aquatic Snake (Thamnophis Marcianus) in a Desert Environment: Implications of Early Timing of Birth and Geographic Variation in Reproduction.” American Midland Naturalist, vol. 143, no. 2, Apr. 2000, p. 453. EBSCOhost, libproxy.estrellamountain.edu/login?url=http://search.ebscohost.com/login.aspx?direct=true&db=a9h&AN=2994839&site=ehost-live.

Sheehy, Coleman M., et al. “The Evolution of Tail Length in Snakes Associated with Different Gravitational Environments.” Functional Ecology, vol. 30, no. 2, Feb. 2016, pp. 244–254. EBSCOhost, doi:10.1111/1365-2435.12472.

Willson, John D., and Michael E. Dorcas. “Aspects of the Ecology of Small Fossorial Snakes in the Western Piedmont of North Carolina.” Southeastern Naturalist, vol. 3, no. 1, Mar. 2004, pp. 1–12. EBSCOhost, libproxy.estrellamountain.edu/login?url=http://search.ebscohost.com/login.aspx?direct=true&db=a9h&AN=12807293&site=ehost-live