Researchers found that even slight temperature shifts can alter the migratory patterns of certain bird species.
研究人员发现，即使是微小的温度变化也能改变某些鸟类的迁徙模式。
Wolves are considered a keystone species in some ecosystems because their presence alters the grazing behavior of deer and elk, which in turn allows young trees along riverbanks to grow undisturbed, stabilizing soil and supporting a wider range of other wildlife.
From a Central Ideas and Details question · Information and Ideas
Which choice best defines “alter”?
C — To change or modify. “alter” means to change or modify.
Which word means “to change or modify”?
B — alter. “alter” means to change or modify.
alter — to change or modify. In Chinese: 改变，修改.
alter is pronounced /ˈɔːltər/.
Researchers found that even slight temperature shifts can alter the migratory patterns of certain bird species. (研究人员发现，即使是微小的温度变化也能改变某些鸟类的迁徙模式。)
modify, change, adjust — all close in meaning to alter (to change or modify).
preserve, maintain — each the opposite of alter (to change or modify).
Yes. alter is on the SAT Prep Easy list — mid-frequency academic words that do get tested. The Digital SAT does not test vocabulary in isolation; words like this one are tested through Words in Context questions, where you choose the word that completes a passage most logically and precisely.
alt(change)+er(verb suffix)