Final answer:
Endangered species and extinction are the main topics discussed in this question.
Step-by-step explanation:
The question relates to the topic of endangered species and extinction.
Extinction occurs when all members of a species die out. Endangered species are those that are at high risk of becoming extinct in the near future. Trapped species are individuals of a species that are confined to a specific location, while endangered species are those that are facing a high risk of extinction. The numbers associated with SPE 1-50, SPE 51-80, and SPE 81-100 represent different groups or categories of species based on their level of endangerment. For example, species in the SPE 1-50 category may be critically endangered, while those in the SPE 81-100 category may be classified as vulnerable. The reference sources provided contain additional information on the IUCN Red List and the conservation status of species.