Regarding 2a/2b:
Taking the last letter from each state to get HEDGEHOG and SNAKE.
Regarding 3a/3b:
Take the middle letter from each state to get SEA HORSE and MARMOT.
Regarding 8a/8b:
Each clue consists of 4 lists of states. The states in each list are path-connected.
For example, regarding 8a:
{Arizona, California, New Mexico, Oregon, Washington} form an L-shaped region.
{Arkansas, Iowa,Louisiana, Minnesota, Missouri} form a vertical line.
{Alabama, Arkansas, Georgia, Illinois,Indiana, Mississippi, Missouri, North Carolina, Ohio, South Carolina,Virginia, West Virginia} form a circle.
{California, Idaho, Kansas, Nebraska,New Mexico, North Dakota, Oklahoma, Oregon, South Dakota, Texas,Utah, Washington} form an N-shaped region.
Together these regions spell LION.
For 8b:
{lllinois, Kansas, Louisiana, Minnesota, Mississippi, Missouri, Nebraska, North Dakota, Oklahoma, South Dakota, Tennessee, Texas, Wisconsin} form a B-shaped region.
{Colorado, Montana, Nebraska, New Mexico, North Dakota, Texas, Wyoming} form an E-shaped region.
{Arizona, Colorado, Idaho, Kansas, Montana, Nebraska, North Dakota, Oklahoma, South Dakota, Texas, Utah} form a..an A-shaped region.
{Alabama, Florida, Georgia, Illinois, Kansas, Kentucky, Minnesota, Missouri, Nebraska, North Dakota, Oklahoma, South Dakota, Tennessee, Texas, Wisconsin} form a.an R-shaped region.
Together these spell BEAR.