"expand their range" is correct and usable in written English.
You can use it when you are talking about increasing the scope of something. For example: "The company decided to expand their range of services to include design and consulting services."
And hard winters have softened, which allows the beetles to flourish and expand their range.
The owners are looking to expand their range of homegrown veg in the near future.
People who think about wild hogs wonder how far they will expand their range.
"They were able to expand their range pretty dramatically, and the teeth complexity implies they ate plants," Dr. Wilson said.
The number of stock killed in North America is small but increasing as wolves expand their range.
Perhaps they will eventually expand their range still further, and hop across the Bristol Channel to the Somerset coast near where I live.
When manufacturers expand their ranges downward to the budget market, cost-cutting risks producing a bad experience that can poison customers' view of the brand.
The study also found that nine lemur species (16% of the total examined) were predicted to expand their ranges while 13 species' (22.8%) ranges remained stable over time.
Unlike jump dispersal, it is not lineage-specific but usually connected to geological or global climatic events that cause several different lineages to expand their ranges congruently.
In fact, warming temperatures have allowed nonnative species to expand their ranges into areas where they previously could not survive and reproduce [6].
How then have long-lived tree species been able to expand their ranges so rapidly while simultaneously tracking relative phenotypic optima so closely?
