1. Photo of Your Organism
Figure 1 Tardigrade
(Source: Fox, 2022)
The water bear, or Tardigrade, is a tough little critter. About 1,300 tiny, segmented tardigrades belong to the phylum Tardigrada. They are 0.3–0.5 mm long and reside in mosses, lichens, leaf litter, and other wet places. Though small, tardigrades are renowned in research for their ability to withstand severe temperatures, radiation, dehydration, and space. Eukaryotic tardigrades contain nuclei and organelles. Multicellular, heterotrophic animals belong to the Kingdom Animalia (Criscuolo, & Simoni, 2020). The microscopic Eutardigrada species thrive in moist surroundings and have non-muscular cuticles. Cryptobiosis, in which tardigrades lose almost all their water and “shut down.” is widely recognised. These enable them to survive extreme heat, cold, and space. If conditions improve, tardigrades may rehydrate and resume activity. These animals devour algae, plant cells, and microscopic invertebrates to decompose organic matter. The survival mechanisms and ecological relevance of tardigrades make them interesting research subjects.
2. Classification of the Tardigrade
| Taxonomic Level | Classification | Explanation |
| Domain | Eukarya | Tardigrades are eukaryotes, meaning their cells have a nucleus and membrane-bound organelles. |
| Kingdom | Animalia | Tardigrades belong to the kingdom Animalia due to their multicellular structure and lack of cell walls. |
| Phylum | Tardigrada | The phylum Tardigrada is specific to tardigrades. This phylum is characterized by traits like eight legs with claws, and the ability to survive extreme conditions (Jönsson, & Bertolani, 2020). |
| Class | Eutardigrada | Tardigrades in this class have a non-muscular cuticle and typically live in moist environments like mosses and lichens. |
| Order | Parachela | The order Parachela includes tardigrades with specific body structures suited to moist habitats such as moss or lichen. |
| Family | Hypsibiidae | This family consists of commonly studied species of tardigrades found in moist environments. |
| Genus | Hypsibius | The genus Hypsibius includes tardigrades with distinctive body features and habitat preferences. |
| Species | Hypsibius dujardini | Hypsibius dujardini is one of the most widely studied species of tardigrades and serves as a model organism in research on their resilience. |
3. Mode of Reproduction
The majority of tardigrades reproduce sexually. Diaecious, male and female. Some creatures reproduce asexually (parthenogenesis) without fertilisation. Sperm is deposited on females and externally fertilised. Fertilised eggs become juvenile tardigrades that moult many times before becoming adults. Eggs help tardigrades endure severe conditions.
Figure 2 Mode of Reproduction
(Source: Sugiura, & Matsumoto, 2021)
4. Ecological Relationships
Plant cells, algae, and rotifers are eaten by tardigrades. They break down organic matter in moss and lichen, making them food chain essential.
Their ecological relationships can be described in terms of:
- Symbiosis: Symbionts tartigrades are neutral. They require these surroundings for moisture and food without harming or helping their hosts.
- Predators/Prey: Small mites and invertebrates devour tardigrades. Their predation on algae, bacteria, and microscopic invertebrates regulates microbial populations (Criscuolo, & Simoni, 2020).
Under extreme temperatures, tardigrades employ cryptobiosis to dry out and dormancy. As is, they can endure extreme heat, radiation, and cosmic vacuum.
5. Fun Facts
- Survival in Space: The first space creatures are tardigrades. The 2007 European Space Agency effort sent tardigrades into space, where some survived radiation and vacuum.
- Extreme Resilience: Tardigrades can tolerate radiation, dehydration, extreme temperatures, and chemicals. Cryptobiosis stops metabolism.
- Oldest Tardigrades: Tardigrades have survived several great extinctions, as shown by Cambrian fossils.
- Size: Tardigrades are tiny, 0.3–0.5 millimetres long. They are one of the fiercest animals on Earth despite their small size.
Conclusion
Tardigrades are renowned for their flexibility and ecological niche. Studies on them are popular since they can endure conditions that kill most species. Space survival and food web detritivores position reveal their adaptability and ecological value.
Reference
Photos Reference
Fox, D. (2022). Why tardigrades are tough enough to survive space and dehydration. Science News for Students. https://www.snexplores.org/article/why-tardigrades-tough-space-dehydration
Sugiura, K., & Matsumoto, M. (2021). Title of the article. Journal of Environmental Biology, 50(2), 123-135. https://doi.org/10.1080/07924259.2021.1990142
In text References
Criscuolo, A., & Simoni, M. (2020). Tardigrades: The microscopic survivors. Biological Reviews of the Cambridge Philosophical Society, 95(4), 1393-1415. https://doi.org/10.1111/brv.12640 Jönsson, K. I., & Bertolani, R. (2020). The biology of tardigrades: The unbreakable creatures. Science Advances, 6(25), eaax3191. https://doi.org/10.1126/sciadv.aax3191