Today’s column marks the official end of Squirrel Week. Before we close out this year’s festivities, Answer Man wants to address some of the questions that came in from readers in the past seven days.

Questions such as this one: “There are thousands of squirrels all over my neighborhood, but I never seem to see any squirrel poop. Why is that?”

Perhaps you are mistaking it for the scat of another animal — a rabbit, for example. Then again, it’s not as if squirrel feces is very distinctive or very large. “You’d never notice it,” said Richard W. Thorington Jr., a curator of mammals at the Smithsonian Institution. Richard assured Answer Man that squirrels do poop.

Speaking of which, Answer Man recently learned something rather interesting: Baby squirrels must be taught to defecate. This fascinating bit of information came from Don Moore , associate director of animal care sciences at the National Zoo. Earlier in his career, Don worked in Syracuse, N.Y., rehabilitating baby squirrels.

Squirrels are among species — deer are another — where the mother uses her mouth to carry her offspring’s poo and pee away from the nest. This is to protect her litter from predators.

“Evolutionarily, that’s a great strategy,” Don said. “The mother’s removing the only thing that can give [the baby] a scent: the pee and poo.” With no scent to follow, predators can’t find the defenseless baby.

The mother’s selfless act is so hard-wired in a squirrel’s very being that babies can urinate and defecate only after being stimulated by the mother licking around . . . down there.

Orphaned squirrels raised by humans risk becoming constipated and bloated. “The gut stops moving,” Don said. “You don’t want that to happen, so you stimulate them. In fact, you have to start stimulating them just to get them to feed.”

Squirrel moms provide stimulation with their tongues. “We don’t recommend that,” Don said. “We would use a warm, damp washcloth.”

Baby squirrels must have their nether regions stimulated at every feeding from birth to about five weeks of age, when their eyes are open and their fur is coming in.

“It’s a wonderful day when they start doing it themselves,” Don said.

Kit Hope of Silver Spring freely admits that she feeds the squirrels in Farragut Square “for my own amusement, not from any deep-seated desire to reach out to our furry friends (who are, after all, cute rats). But that being said, I’d like to know what’s healthy and easy to feed them.”

I asked Debi Klein, who runs the Backyard Naturalist in Olney, for recommendations. “Squirrels love unsalted raw or roasted whole peanuts in the shell; split peanuts (shelled) and sunflower seeds,” she wrote in an e-mail. “These would be good ‘feeding in the park’ foods. Always unsalted!”

A reader named Pat said her dog loved to sit facing a floor-to-ceiling window and bark at the squirrels outside. “Sometimes the squirrels would sit on the fence facing our window and seem to taunt her knowing she couldn’t get to them,” Pat wrote. “Is that possible?”

I asked Robert Lishak , a biologist at Auburn University. He said the first time the dog barked at a squirrel, it ran away. But as it noticed that the dog was not able to chase, the squirrel became habituated to the dog’s presence. Wrote Robert: “The squirrel’s instincts would have caused it to keep a close eye on the dog so it would likely face in the direction of the dog as long as the dog was visible, which might give one the idea that the squirrel was taunting the dog.”

A reader named Joy asked: “What do squirrels add to the urban landscape, other than absolute cuteness? Does it have anything to with hiding acorns, which grow grand oaks?”

Yes, squirrels do that. The critters, write Thorington and Katie Ferrell in “Squirrels: The Animal Answer Guide,” “are important ecosystem engineers and play a significant role in the regeneration of forests around the world.”

Since they don’t find every nut they bury, squirrels are responsible for countless seedlings coming up every spring. In less-urban areas, they move nuts into areas afflicted by forest fires, helping to regenerate the scorched land. Some squirrels have a taste for truffles, the fruiting bodies of certain fungi. The fungi have been shown to help trees such as the long-needled pine absorb nutrients from the soil. By spreading fungal spores, squirrels help the trees.

Finally, squirrels are food, maybe not so much in Lafayette Square, but in many habitats, where everything from owls to snow leopards depend on the protein in squirrels to survive.

Humans — even Washingtonians — could probably survive without squirrels. But Answer Man hopes we won’t ever have to.

To test your squirrel knowledge, go to wapo.st/squirrel-quiz. And to read previous columns by John Kelly, go to washingtonpost.com/johnkelly.