I never thought I’d know a bunch of two-humped camels by name. But life-when you’re lucky-is full of surprises.

Now that I’m into my 60s and have been retired for a bit, I seldom have trouble finding exciting volunteer opportunities. I’m convinced it’s vital to keep pushing yourself onto new turf, taking on different roles and mixing with people of all ages. But there’s also nothing like a little cash flow to supplement one’s pension to make you feel, shall we say, more validated in the process.

I used to say it wouldn’t matter to me if I ended up flipping White Castle burgers or stocking shelves at Jewel. What was I thinking? I’d rather set my hair on fire. After 35 years of teaching, I know I’ve got chalk dust in my blood. I need to be a know-it-all ham, imparting wisdom to a captive audience.

For years I’ve been a volunteer docent at places like the Frank Lloyd Wright Home & Studio and Pleasant Home in Oak Park. But where do they pay you to be a tour guide? One day it dawned on me: The Motor Safari Trams at Brookfield Zoo. I recalled them from years ago when my kids were tots. Did such vehicles still exist?

Immediately I went on-line to apply and, amazingly, a couple of days later, someone called me to schedule an interview. Before I knew it, I was in training.

Orientation to Guest Services is a crash course in the natural order of life at Brookfield Zoo. At the top, of course, are the animals. Next come the guests. Many hundreds of workers are just thrown into the mix to make sure both groups have a good experience most of the time.

No dead spaces

In case you’ve not been to the zoo for a while, the Motor Safari Trams are long-90 feet-motorized, open, bus-like vehicles, formed by three conjoined cars, chock full of blue benches. The trams don’t run on a track but snake among the zoo visitors. The driver moves very slowly through the entire zoo, with four stops or “stations,” corresponding to the compass-north, west, south and east. The guide, hanging on the end of the last car like a streetcar conductor, speaks non-stop into a microphone during the entire ride.

Every morning our small army of tramsters cleans the open cars, sweeping them out to remove leaves, sticks, juice boxes or Frito bags under the benches, then wiping down and polishing the blue seats with spray cleaner and rags. After a quick meeting with our bosses, we’re assigned to specific routes in rotating pairs.

Once the gates are thrown open, from then on everyone is in a constant cycle. You are always working with someone else. One of you drives; the other is the guide on the microphone. Since you work together closely, you really get to know your partner pretty well.

For my initial few days I had the luxury of studying zoo material in a big black binder that’s provided for all the rookie guides. I rode around on the back of many trams listening to continuous tours by my co-workers, so I could develop a “script”-my own spin on the animals and sights we’d be passing on our roughly 45-minute tour around Brookfield Zoo.

The goal is to keep talking at all times. Our training manual stresses there are to be no dead spaces on one’s tour. “Silent pauses are occasionally allowed but they should not exceed 10 seconds in duration. Never ‘abandon’ your listening audience: you’ll find it extremely difficult to recapture their attention.”

As you put your tour together, you stockpile lots of diverting tidbits to throw in, developing a running patter that will be enjoyable to hear, not a dry recitation of endless encyclopedic trivia.

“Fill all the time it takes to pass an enclosure,” the zoo manual advises. Note the use of the word “enclosure.” We must never, ever say the C-word: cage. When Brookfield Zoo opened in the 1930s it was acclaimed for leading the movement toward bar-less, open grottos and natural “yards” surrounded by moats where the animals could easily yet safely be observed.

Whenever possible, toss in humor to spice up your narration. “The male lion sleeps up to 20 hours a day,” I tell my tours. “Almost as much as the average American college student.”

We’re also encouraged as much as possible to refer to our animals by name. Not just their species name, mind you, but their actual zoo-given first names, as in, “These are our four North American bison: Ron, Drue, Becky and Judy.”

This was a particular challenge as I’ve now reached that point in life where I often get blurry trying to remember the correct names of most of my friends and family members, let alone assorted zebras, elephants and sloth bears.

Hudson, our baby polar bear, was probably our most popular and crowd-pleasing animal this past summer. His mom, Arki, has been teaching him to swim. Surprisingly, these Arctic aquatic critters don’t know how to swim naturally. Of course, we’re never supposed to allow people on the trams to stand up at any time while we’re moving, and this is especially difficult while passing through Bear Country as goofy little Hudson is playing, diving and working the crowds like a finalist on “American Idol.”

Amazing animals

As you might imagine, it wasn’t long before I found myself boring my friends back home with endless animal lore. Would you believe giraffes have 18-inch purple tongues that can grasp and strip leaves off branches? And did you know giraffes never sit down or lie down, even when giving birth, and that they sleep for only 5 minutes at a time-and never more than 20 minutes total per night? As I’d excitedly spew all this information, my friends and family members would glance back and forth at one another knowingly-when they weren’t rolling their eyes.

But most of this stuff still amazes me. Would you believe Cookie the cockatoo was a resident of the zoo when it opened on July 1, 1934, and he’s still alive and well 73 years later?

Many of my fellow guides this summer were college kids; others were in my age group. I’ve enjoyed the mix, and the contrast is often amusing. On breaks, some of us would talk about nursing hangovers or changing our majors while others discussed our latest surgical procedures or the cholesterol and fiber content of our snacks.

Working the Motor Safari Tram makes for a very long day, especially if the weather is perfect and the zoo’s packed. The driving terrified me at first; I felt like Desi Arnaz in the “Long, Long Trailer.” Since many zoo guests believe they’re in a “magic kingdom” where nothing can hurt them, they will meander, oblivious, right in front of your 90-foot moving tram, casually chatting on their cellphones while pushing their offspring in a stroller. This can be harrowing.

Since I hadn’t worked outside for many decades, I came home exhausted my first few days. But I quickly found myself surprised by how much I enjoyed the job. I actually liked wearing the uniform-the khaki shorts and navy blue polo shirt with the dolphin logo made dressing for work so easy. And I never minded wearing the photo I.D. For one thing, the large print made learning my co-workers’ names easier. I enjoyed being part of that army of hundreds who opened the zoo every morning.

I’m convinced there’s a certain “disconnect” when you retire-too much “aloneness” (not loneliness). The freedom is fabulous. But if you don’t have enough to really keep you involved, you have too much time to ponder and worry about stuff that either doesn’t matter or that you can’t change anyhow. So it’s been fun and fulfilling to be part of a huge, busy organization. I’m basically a loner yet I’m also a people person. I’ll never fully make sense to myself.

My immediate bosses are a couple women who were consistently fair and impartial. This was something new for me, coming from a lifetime of working in a public high school system under leaders who routinely acted like erratic dictators in some banana republic.

Some kids never grow up

Part of the Motor Safari Tram guide rotation pattern involves occasional half-day duty on the zoo’s big carousel. It’s a popular, year-old attraction featuring 72 hand-carved, hand-painted zoo animals and several chariots-not your typical merry-go-round horses. Riders can mount critters ranging from rhino and ostrich to gorilla and tiger. There’s even a manatee, a praying mantis and, believe it or not, a giant red-eyed cicada.

Running the carousel involves scanning tickets, loading up all the riders, making safety announcements on the loudspeaker (“face forward, no side-saddle, no changing animals while the ride is moving”) and, of course, operating the ride itself. Speakers blare a non-stop assortment of vintage calliope music and rock/disco oldies.

Occasionally the same song will recycle in close repetition. I once had the Village People’s “Y.M.C.A.” endlessly trapped inside my head after leaving the carousel to go work the trams.

Running the carousel isn’t tricky, but I was plagued by flashbacks to the climactic scene in Hitchcock’s “Strangers on a Train” where a crowded merry-go-round goes violently out of control, then crashes. I’ve clearly seen too many movies.

Working closely with the public has mostly been a delightful experience. I’ve chatted with people from all over the globe. And if you’re able to talk long enough, there’s always a “small world” angle. Last week I met a young woman who was a new teacher at my old high school.

The little kids invariably get crabby and whiny late in the day, but so do I. It’s fun to see the families together, enjoying one another, making memories. The grandparents are especially a riot to watch, cavorting with their little guys on the carousel, teaching them to wiggle and sing along to oldies like “Splish-Splash” or “Runaround Sue” while they ride. Of course, you must never ask, “Will you be accompanying your granddaughter?” Nowadays that wizened, white-haired gent just might be her daddy.

It never ceases to amaze me how people much larger and way heavier than I am who are accompanying no small children will proudly present their ticket, beaming broadly, then climb up on the lion, panda or dolphin. There’s a little kid somewhere inside all of us, thank God.

Brookfield Zoo has been a hoot.