The extinction of animals
foreign species in ecosystems change the relations between native organisms that live there, contributing to their extinction;
destroying natural ecosystems contributes to the disappearance of habitat and home ground of wild organisms;
using pesticides in farming causes the death of many species of plants and animals, both on land and in water.
to mention and describe the main reasons for animal extinction;
to give examples of extinct animals and animals on the verge of extinction in Poland.
Right now, on a global scale there are more than 16 thousand animal species that are on the verge of extinction. Those are around 1% of all described species. Among the endangered species, 12% of them are the vertebrates. The reasons for their extinction are, like in the case of plants – mainly anthropogenicanthropogenic. Those are: disappearance or change to their natural habitat, pollution to the environment, excessive exploitation of resources (killing of animals for their meat and fur and other precious products, overfishing of fish and seafood, hunting wild animals for collectors), intentional elimination of species considered pests, changes of interspecies relations in ecosystems, and farming.
In the last 100 years in Poland, 36 species went extinct, even though they are still present in neighbouring countries. Among them there are 14 species of vertebrates, e.g.: souslik, European Mink, griffon vulture, great bustard, lesser kestrel, Atlantic sturgeon, and 22 species of invertebrates, among which there is freshwater pearl mussel. In our fauna there are 2 species missing that went completely extinct - aurochs and Eurasian wild horse.
There are rather few species that are on the verge of extinction in Poland. There are only 329 of them, which is around 1% of 33 thousand species that live in our country. Among them there are as many as 93 species of vertebrates, which is almost every 4th one.
Species that are critically endangeredcritically endangered and whose numbers are small, which means they can go extinct at any time is 91: 24 of them are vertebrate species, e.g.: grouse, chamois, European roller, porpoise, greater spotted eagle, sandwich tern, peregrine falcon, and Aesculapian snake. There are also 67 species of invertebrates, e.g. small lappet moth, goldstreifiger, apollo butterfly, Ripart's anomalous blue, and Chilostoma cingulella.
Select all the statements that are true.
- Nowadays, extinction of animals is mainly caused by anthropogenic.
- Several times in history humans caused extinction of species that they hunted.
- Changing forest ecosystems into farmlands can cause the extinction of wild animals.
- Using chemical substances to protect plants makes possible to preserve animal species that are going extinct.
- Reptiles are particularly prone to diseases caused by pollution and climatic changes.
- Introducing an invasive species into the ecosystem never caused the extinction of any other species.
Which from the species below were completely wiped out by human activity?
- Eurasian wild horse
- aurochs
- moa birds
- dingo
- Tasmanian wolf
- great black cormorant
Match the name of the animal with the cause which made it go extinct or which decreased its population.
extermination of species that were its source of food, frequent crossbreeds with domesticated form, decreased area of natural habitat, pollution of the environment, hunting for meat and skin
| Haast's eagle | |
| Eurasian lynx | |
| freshwater pearl mussel | |
| aurochs | |
| wildcat |
How was this lesson? Did you like it? Finish selected sentences.
1. Describe the cases of animal going extinct according to the following categories: excessive exploitation of resources, disappearance of natural habitats, change of ecological relations.
2. Superstitions and fear are some reasons for killing animals. Give few examples of species wiped off for those reasons.
Keywords
extinction, elimination, changing of ecosystems
Glossary
antropogeniczny czynnik – czynnik oddziałujący na środowiska i zamieszkujące je organizmy, wywołany przez człowieka lub powstały przy jego udziale
krytycznie zagrożone gatunki – gatunki uznane za zagrożone wyginięciem przez Międzynarodową Unię Ochrony Przyrody (IUCN)