You can tell if matter is conserved if the substance changes . If the substance changes then matter has been conserved .
The ground finches adapted to have larger beaks to eat the bigger seeds in the drier seasons. This means over the years only the bigger beaked finches could survive to reproduce.
<span>Perhaps surprisingly, lakes and rivers constitute a tiny proportion of the world's total freshwater, so answer (b) is correct. Most of the freshwater on our planet is in fact locked up in ice and glaciers, some 68%. The majority of the rest, 30%, is actually underground, in springs and other groundwater feeders. That leaves just 2% that makes up all the rivers, lakes, ponds and other visible freshwater reservoirs that we see in our day-to-day lives.</span>
They are considered invasive because they out-compete native fishes for resources
