The teen was having a fit. He was hungry, and his mother had left to go to work. His father couldn't calm him down and finally gave up trying. The teen stomped around, squawking. Sound familiar?

Except we're not talking about humans here, but rather birds — a juvenile Nazca booby a few feet away from me on an island in the Galapagos that is home to more than half a million birds. The bay we're anchored in — Darwin Bay at Tower Island (also known as Genovesa Island) — is in fact a caldera formed by an ancient volcano, and we walk around looking at more birds than I've ever seen in one place: red-footed boobies, blue-footed boobies, gulls and frigates, which ignore us just like teens often do. We hike up steep steps to the rim of the caldera and watch the Nazca boobies' mating dance — the male whistles to try to attract a female.

All week, as we cruise the Galapagos Islands off the coast of Ecuador, we joke about the parallels between the amazing creatures we encounter here and human family behavior.

We pose with giant tortoises that ignore our presence, and we try not to disturb the marine iguanas sunning themselves on the rocks. Sea lions swim circles around us in the water. We hike over black lava fields and snorkel with sea turtles and stingrays. I feel like we've stumbled into an episode of "Nova."

This wouldn't be everyone's first choice for an expensive vacation. There are no beach chairs or tiki bars on these protected beaches, where tourists may only venture with a guide. But this is an adventure that we'll never forget, starting with those sea lions we spotted on San Cristobal Island, snoozing on rowboats as if they owned the place.

Along with three other families, we've signed on for a weeklong cruise organized by Seattle-based Wildland Adventures (http://www.wildland.com), a member of the Trusted Adventures consortium of travel companies (http://www.trustedadventures.com).

Our home for the week is an 83-foot boat called Flamingo 1, operated by Ecoventura (http://www.ecoventura.com). It's comfortable but certainly not luxurious. We're surprised that we can find room for all of our gear in the small cabins. There are perhaps 85 tour boats in the Galapagos Islands, from a 100-passenger cruise ship to small boats that sleep four or six people. Some of the tour boats are yachts, including one designed to replicate Charles Darwin's ship, the HMS Beagle. Ours seems just the right size, sleeping 20 passengers. It has a crew of 11, including two experienced naturalists, Harry Jimenez and Orlando Romero, who make every excursion an adventure — even for the 8-year-old twin boys on board.

Manolo Martinez, the captain, has five children at home, he tells us over dinner. He invites a different family to dinner each night. We're a varied group: my husband Andy; Matt, 22, who's going to start an exciting new job when he gets back; Reggie, 20, our college junior; and high-schooler Melanie, 15. There are also the Peets, from Seattle, with Summer, 12, and Graham, 9; and the Strausses, from Bethesda, Md., with twins Joshua and Daniel, 8. Then there is Subodh Das of Lexington, Ky., who is here with his daughter Mona Mullin, 35; friend Diane Moore and son Som Das, 25. They try to take an exotic trip every year, Subodh says, his children joking that they're happy to travel with dad since he's paying. "And I'd rather leave them memories than money," added Subodh, a divorced engineer.

A family adventure

Many families we meet seem to agree with that philosophy. These remote islands off the coast of Ecuador, where the wildlife (especially the giant tortoises) inspired Darwin's work, have emerged at the top of many families' travel wish lists. Where else can you snorkel with sea lions or watch a sea lion nurse her pup? Even at a cost of more than $10,000 for a family of four, adventure companies such as Wildland Adventures, Austin-Lehman Adventures (http://www.austinlehman.com), Abercrombie & Kent (http://www.abercrombiekent.com) and Thomson Family Adventures (http://www.familyadventures.com) report increasing interest in Galapagos trips designed for families.

"We're not the kind of family that likes to go and sit on a beach," Sam Peet said.

"Definitely not," 12-year-old Summer said as she raced off to splash in the surf, sea lions lazing nearby.

Animals and astronomy

The beach where we've stopped to swim and snorkel is full of sea lions — mamas and their nursing pups, frisky adolescents, fathers marking their territory. Every day is a different island and a different adventure. We see Sally Lightfoot crabs, bright red against the black lava rocks; great blue herons; penguins (yes, there is a warm-water species here); and even a short-eared owl, which is small and is apparently the only owl on the planet to hunt food during the day (no predators for the owls to worry about). Frigates hitch a ride on the mast of our boat, much to the kids' delight.

Before dinner each night, the naturalists tell us what we'll do the following day. Important clothing details — hiking shoes versus flip-flops, shorts versus swimsuits — are discussed. It's nice to leave all the planning and cooking to others. We do have to keep track of our own snorkel gear and wetsuits (provided by the boat) and our beach towels. That's not as easy as it sounds with the gear in identical mesh bags.

And because we're so close to the Equator, we see stars in both the Northern Hemisphere and Southern Hemisphere at night. They are so bright. I can't believe that we're here in the Pacific Ocean at the center of the globe.

"You may not remember the food, but you'll remember everything we saw," Som Das said.

"This has really exceeded expectations," said Steve Strauss, whose only worry is that his two boys aren't old enough to fully appreciate this trip.

Remember, it's still family

But even in paradise, kids get hot and tired, siblings bicker, teens want to get away from their parents, the boat rocks too much some nights and the food gets tiresome. It's all part of the adventure, we tell each other.

On a small boat like this, everyone must make an effort to get along. It's not as if you can go elsewhere and get away from anyone, whether your own family or others on board. There's no entertainment except that which we supply ourselves.

When we're not hiking, snorkeling or exploring, we congregate on the top deck with cushioned chaise lounges, shaded from the sun, to read, talk or take a snooze — just like the sea lions. The kids play Scrabble and cards. The crew members do all they can to make us happy.

"Remember, you're in paradise," the naturalists keep reminding us.

How can we forget?

— For more Taking the Kids, visit http://www.takingthekids.com, where Eileen Ogintz welcomes your questions and comments.