Question

fewer butterflies, but why?
the new study looked at 534 butterfly species in the u.s. for every 5 butterflies seen in the year 2000, there were only 4 in 2020. about one in three species showed serious drops in numbers. over 100 species had their numbers drop by more than half.
so why are butterfly numbers dropping? the scientists say there are three main reasons, and they are pretty much due to people.
people are building more roads, homes, businesses, and other developments. they are cutting up and stamping out meadows where butterflies once flew. there is less land for butterflies to live.
climate change is another problem. this is the significant change in the climate of earth over a long period of time. it can happen naturally. but today, climate change is largely caused by human activities. rising temperatures due to climate change are drying out plants in the areas that remain. every butterfly was once a caterpillar, and caterpillars depend on plants for food.
conditions that are bad for plants are bad for butterflies. many butterfly species are doing better in the northern parts of the areas in which they live, the scientists found. this suggests the butterflies are flying further north where it is cooler to keep cool themselves. the states in the hot and dry southwest saw the largest drops in butterfly numbers.
pesticides are the third and likely most important reason behind the drop in butterfly numbers. pesticides are mostly used for farming. a pesticide is a substance used to kill, keep away or control certain forms of plant or animal life that are considered pests. but pesticides can kill butterflies, too.
the scientists hope their findings act as an alarm bell for people who love butterflies. because there is still hope. unlike many other animals in trouble, insects breed quickly. people can create more butterfly meadows. farmers can limit their use of pesticides. if given a chance, butterfly numbers can bounce back.

Explanation:

Since no specific question is provided about this text, it's not possible to give a targeted answer. If you have a question related to this text, such as analyzing the reasons for butterfly population decline, identifying the disciplines/subfields related to the study (e.g., Biology for the butterfly species study, Environmental Sciences for the impact of human activities and climate change), or something else, please share it so that I can assist you.

Answer:

Since no specific question is provided about this text, it's not possible to give a targeted answer. If you have a question related to this text, such as analyzing the reasons for butterfly population decline, identifying the disciplines/subfields related to the study (e.g., Biology for the butterfly species study, Environmental Sciences for the impact of human activities and climate change), or something else, please share it so that I can assist you.