Now you will examine the biodiversity crisis using the Hawaiian Islands as a case study. This archipelago is geographically diverse in size, elevation, and habitat type and is historically rich in biodiversity.
Hawaii's variety of plants and animals is an example of how isolation can lead to the emergence of new
species. This has produced many very specialized species, most of which are endemic, meaning they are
found nowhere else on Earth. Though there is a variety of species, these species are particularly
vulnerable to the effects of introduced species, habitat loss and fragmentation.
What does the article mean by "these species are particularly vulnerable"?

americans began to notice growing differences between the northern and southern sections of the country. there were more people living in cities in the north, which made it more urban. more people lived on farms in the south, which made it more rural. while many people were farmers in the northern states, there were now other ways to make a living, such as working in mechanical cotton gins factories manufacturing cloth, tools and other goods. people in the north supported high tariffs on goods imported from europe because the extra cost encouraged people to “buy american” instead. in the southern states, planters did not like tariffs because they sold most of their production to europe and bought their tools from there as well. southerners believed the protective tariff was something that only northern factory owners keep their profits high. so the southern politicians came up with an idea. they would opt out. they would simply ignore the protective tariff. it was ‘null and void’ in south carolina. the state would not collect the taxes on goods imported into south carolina, no matter what the president said they had to do. this decision led to the nullification crisis.