Photosynthesis: Yellow-spotted salamanders are the only vertebrate animals known that can photosynthesis like plants! When in the eggs, these salamanders have a special relationship with the algae 𝘖𝘰𝘱𝘩𝘪𝘭𝘢 𝘢𝘮𝘣𝘭𝘺𝘴𝘵𝘰𝘮𝘢𝘵𝘪𝘴. It grows inside the egg feeding on nitrogen produced by the larval salamander, while producing oxygen, this allows the salamander to develop in environments with little dissolved oxygen. As the salamanders hatch and develop into adults, the algae becomes incorporated into the salamander’s cells through a process called endosymbiosis. Here, they produce energy much like a plant’s chloroplast, by converting carbon dioxide and water into sugars and oxygen, a process fueled by the sun’s energy. Being nocturnal and living primarily underground, the yellow-spotted salamander is rarely in direct sunlight and therefor rarely photosynthesis. Because of this, the exact relationship between these organisms is still not yet fully understood.
Colour Morphs: Piedbald Nicknamed “Hermione”, this individual has a rare pigment mutation often described as piedbald or leucistic. This means that many of her cells cannot produce melanin, the chemical used for pigment. Because this only occurs in certain areas of her body, it gives her a “panda” or “dairy cow”-like appearance. Only a handful of these special yellow-spotted salamanders have been observed and all have their own unique pattern allowing them to be recorded year after year. One individual, recorded by Don Scallen and nicknamed Calvin, was first found breeding in 2010 and every year since, making him at least 15 years old in 2023, as it takes roughly two years to reach sexual maturity. By recording these easily identifiable individuals, it gives an idea of the specie’s site fidelity, their habit of returning every year, not only to the same breeding pond but to the same part of the pond, a range of roughly one metre squared for Calvin.
|
Colour Morphs: Eggs Every year, in early spring, yellow-spotted salamanders migrate to their breeding ponds to lay eggs. The eggs of these salamanders are laid in large clumps of up to 250 eggs at a time, and are often attached to submerged vegetation. There are however, three “colour morphs” of eggs that can be found. The first is the clear eggs which often look like the eggs of other amphibians such as frogs and other salamanders but have a green hue to them. The second morph is the white morph which is opaque and the larva are hidden. The third morph is an intermediate between the two where the eggs are only somewhat clear. The white egg masses are caused by the concentration of hydrophobic protein crystals in the outermost layers of the eggs. In the clear eggs the proteins on the outside of the eggs are instead water soluble and don’t react in the same way, causing them to remain clear. Just as colour mutations in nature are caused by an individual’s genetics, the morphs of egg masses are caused by the genetics of the mother, and can be inherited.
Reproduction: Yellow-spotted salamanders traditionally breed in small temporary ponds fed by melting snow and ground water. Not all however read the field guide as one population in Southern Ontario has been found breeding in streams! Many males will congregate in a small stream fed by a permanent pond. The males drop spermetaphores while the females swim down stream to collect them. Some of these males have never been to the actual pond and will return to the same part of the stream year after year. After collecting the spermetaphores, the females fight the current to return to the main pond, and lay their eggs. The reason for this differing breeding strategy remains unknown but may give clues as to the rise of other stream dependent mole salamanders and their ability to adapt.
Sources:
Frazer, Jennifer. "Algae Living inside Salamanders Aren't Happy about the Situation." Scientific America, 18 May 2018, blogs.scientificamerican.com/artful-amoeba/algae-living-inside-salamanders-arent-happy-about-the-situation/. Accessed 2 Nov. 2021. Ruth, Benjamin C., et al. "A Molecular and Functional Evaluation of the Egg Mass Color Polymorphism of the Spotted Salamander, Ambystoma maculatum." jstor.org, Journal of Herpetology, Sept. 1993, www.jstor.org/stable/1565152. Accessed 2 Nov. 2021. Scallen, Don. Personal interview. 21 Apr. 2023. "Spotted Salamander." Ontario Nature, 2021, ontarionature.org/programs/community-science/reptile-amphibian-atlas/spotted-salamander/. Accessed 2 Nov. 2021. |