The ancients of our planet
Ostracods are microscopic crustaceans that have two interlocking carbonate shells. These organisms have been found since the Cambrian/Ordovician period and up to the present day, so their lifespan is as much as 490 million years! This is the most abundant group of crustaceans. It is believed that the number of species of ostracods can reach up to 65,000, including current and extinct species. Ostracod communities are among the most variable taxonomic groups of crustaceans, as are their modes of reproduction. Some populations reproduce asexually, that is, parthenogenetically (therefore only females live in such a community).
In other populations, most ostracods reproduce sexually, and in others, both methods are equally popular. It is very interesting that sexually reproducing organisms lay eggs that can withstand extremely poor environmental conditions, and are spread by the wind to a height of tens of kilometers. It is also worth noting that ostracod species living in warm regions are able to glow, or in scientific terms, bioluminescent – to create light during certain chemical reactions in the body.
Ostracods survive in a variety of habitats: cold and deep seas, shallow warm lakes, hot springs or even moss and crevices between the sand. High and low pH, high salinity, extremely wide temperature range do not prevent these organisms from living.
Live sensors
These crustaceans are one of the few groups of aquatic organisms that are sensitive to their environment. The chemical composition of ostracod shells is quite complex – they contain more than 25 types of microelements absorbed from the environment where the crustaceans live. As a result, ostracod studies are very valuable, and the data are used in biostratigraphy, paleoenvironmental and biogeographic analyses. In this way, it is possible to obtain knowledge about the temperature and salinity of the environment, a lot of detailed information about the chemical and physical ecology of aquatic environments. In other words, to go back in time and “see” what Earth looked like in the very distant past. Many of us can only dream that we will remain useful and interesting to future scientists millions of years from now…
After visiting the Science Festival event “Ostracods – microorganisms living from the Ordovician to the present”, which took place on September 13. 11.00, 11.30, 13.00 and 13.30 will take place in auditorium 222 of the Institute of Geosciences of the VU Faculty of Chemistry and Geosciences (MK Čiurlionio str. 21/27, Vilnius), you will look through a microscope at living and extinct species of ostracods, learn about their ecology and biology, learn where to look for them and how to recognize them. Registration is required.
The author of the text is Simona Rinkevičiūtė.
2024-09-05 23:11:27