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Planet Earth

Respect Your Elders: How These Plants and Animals Rely On Their Parents

From dolphins to redwoods, species learn from — and rely on — their parents.

By Gary FergusonNovember 13, 2019 6:00 PM
Tree-Dolphins
(Credit: Angela Lau)

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Somewhere in the warm, clear waters off the coast of Australia, a mature bottlenose dolphin is swimming with her daughter. It’s dinnertime. But, instead of chasing down a fish in open waters like she usually does, mom swims over to a basket sponge growing on the ocean floor. In a deft move, she breaks off a piece of the sponge, then fits it snugly over her rostrum — her beak. It’s hard not to wonder what that curious, watchful youngster might be thinking about all this. Are you going to eat that sponge? Are we playing?

With the sponge secured on her beak, the older dolphin starts sweeping her head back and forth across the ocean floor. She’s looking for bottom‐dwelling fish like the sand perch, which hide themselves on the floor of the sea under layers of sand. As for the sponge stuck onto her rostrum, it allows her to clear away the sand without injuring herself on broken chunks of coral, or maybe even suffering the sting of another bottom dweller, the scorpion fish. The extra work it takes to catch a fish like the sand perch is worth it because bottom dwellers tend to be fattier. And for a dolphin, fattier means more nutritious.

Sure enough, after a few minutes, a sand perch flushes. The fish dashes off for a few yards and then hesitates, waiting for a moment before burying itself in the sand again. In that brief pause, the elder dolphin shakes off the sponge, surfaces for a breath, and then comes down and snags the sand perch before it can rebury itself. She then passes it to her daughter. And with that, the younger dolphin hasn’t just gotten a good meal; more importantly, she’s learned a powerful hunting technique — one that years from now, she’ll pass along to her own offspring. 

Orca Apprentice

In another ocean, this one 10,000 miles to the north, orcas in the frigid waters of the Arctic are showing off some hunting tricks of their own. Having spotted a sea lion on a small ice floe, three adult whales come together side by side, about 50 yards away. As if on cue, they quickly swim in unison toward the sea lion, submerging together just feet from the edge of the floe. The result is dramatic. The diving bodies of the three whales create a line of big, fast‐moving waves that roll across the ice, knocking the sea lion into the water. A young whale is nearby, watching all this unfold.

Sea Lion
(Credit: Angela Lau)

It’s only one of many clever tricks the young whale will observe and learn. Less than a mile away, a group of five orcas is coordinating something even more complicated. Two whales swim out a few hundred yards, turn around, and then start slapping their massive tales against the water. The sound of that slapping, which can be heard hundreds of yards below the surface, alerts nearby fish to the whales’ presence; in no time, those fish start moving in a line away from the sound, unaware that they’re essentially being herded by the whales. Meanwhile, in the distance, the other three whales have gathered in the deep. At exactly the right moment, the trio blows a massive net of air bubbles that rises to the surface and, for a short while, actually traps the fish, holding them just long enough for other orcas to swim over and feed.

All around the world, on every continent and in every sea, wisdom is flowing from mature adults to the less experienced. Meerkats are teaching their young how to handle the scorpions they find so tasty without getting stung. Chimpanzee leaders are soothing chimps who just lost fiery arguments with their cousins, sitting with them as their anger settles. Wolf leaders are guiding less experienced members of their packs across miles of rugged mountainscape — and, when they finally find elk, showing them how to hunt in a way that reduces the risk of being kicked. Older orangutans in Sumatra are teaching their offspring the complicated work of building a proper sleeping nest in the branches of the trees — lessons that may stretch across four or five years. 

Whales
(Credit: Angela Lau)

Even ants can be thought of as teachers. Somewhere on a grassy patch of ground in France, a female rock ant has found a valuable food source about 10 yards from the nest. On returning to her home, she gets the attention of a young ant, whom she leads back to the food source. As the pair travels, the leader pauses every so often for the following ant to get its bearings by taking in vertical landmarks. In this way the student memorizes the route, which will allow it to return to the food source later on its own. At the end of each of these brief pauses, when the follower is fully oriented, it taps the leader on the back and the pair continues on its way.

In nature, the strongest creature cultures are those that balance the energy and strength of youth with the experience of those who’ve been in the game of life for a long time. The more social the species, the more valuable its mature leaders — those who can apply their experience to a wide range of needs in their communities. This, then, is leadership based not so much on dominance, but on reputation and relational skill.

Pachyderm Pupils

Elephant leaders who stand at the top of herd culture have decades of experience not only learning the nuts and bolts of survival — things like how to find water in a drought — but also negotiating personality and behavioral issues among the other elephants. It takes years of paying close attention for an elephant to learn what to do when two individuals in the herd, or even two groups, aren’t getting along. 

In the 1980s and ’90s, a group of male elephants from South Africa, orphaned when they were young, grew up to be extraordinarily aggressive, getting into fights they had no business being in — and incredibly, over a period of 10 years, killing more than a hundred rhinoceros.

Decades later, research by psychologists at the University of Sussex revealed how the loss of elder wisdom among elephants could cause problems in the young. The research, which they published in 2014 in PNAS, took place with another orphaned group of males in South Africa’s Pilanesberg National Park. The scientists wanted to compare the social skills of that group with those of a group of elephants in southern Kenya’s Amboseli National Park, in which the young had retained all of their familial connections.

Elephant Family
(Credit: Angela Lau)

Each group of elephants was exposed to audio recordings of different vocal calls — their own as well as those of elephants they didn’t know. The calls from strangers were from elephants that varied widely in both age and size, which basically means that each voice would’ve conveyed a different social ranking in the herd. Researchers with video equipment recorded the herds’ reactions, taking special note of bunching behavior, which elephants display under perceived threats, as well as the extent of their smelling and listening behaviors.

The elephants from Amboseli, whose families were intact, scored high on discerning familiar voices from those of strangers, keying in on what could’ve been actual danger from unfamiliar animals. They were also able to distinguish unknown elephants of different ages, appropriately showing more caution — and more defensive responses — when they heard the voices of older animals. This ability alone — to figure out the status of a stranger — is critical for creatures who live in complicated social networks, coming into contact as they do with hundreds or even thousands of other individuals. It’s essential for keeping conflicts to a minimum.

Yet the orphaned elephants of Pilanesberg had no such abilities. They failed to discern friend from potential foe, as well as older leaders from younger, less dominant animals — deficits that could have deadly consequences in the wild. 

Tree Trainee

It’s pretty easy to appreciate the value of elders in the animal world. But as it turns out, maturity can be equally valuable in the plant kingdom. While older trees may not teach in the way we understand that term, they do share and communicate, and those actions are in full service of nurturing the community.

To get a better look at such elder sharing, we might make a morning visit to the magnificent coastal redwoods of Northern California. The shade would be deep and soft, with patches of low fog kissing the tops of the oldest, tallest trees. Starting as a seed only an eighth of an inch across, these redwood trees have grown to staggering proportions — more than 30 stories tall and weighing in at 6,000 tons. Having sprouted in the earliest years of Christianity, they’re among the longest-living life‐forms on the planet.

Every time we take a step on the soft, needle‐strewn ground under these giants, directly beneath that single footprint could be as much as 10 miles of tiny fungal strands woven through the soil. Through these complex and efficient fungal networks, the robust trees are communicating with one another.

Redwood-Trees
(Credit: Angela Lau)

The healthy elders of this redwood forest are consistent, generous users of this network. In a given year, the big trees will send countless special deliveries through the fungal web — many bound for younger trees that are not only more vulnerable to disease but, because of their size and growing conditions, less able to muster the carbon they need to grow. In some cases, elder trees may even use the web to prompt young saplings to activate useful genetic traits, such as a heightened resistance to drought.

Several years ago, University of British Columbia forest ecology professor Suzanne Simard, a pioneer researcher of these fungal, or mycelium, networks, posed an intriguing question. While it’s clear that trees communicate and exchange goods, could it also be that an elder tree is especially prone to tending to its own young family members? Simard’s research suggests that’s exactly what’s going on. The biggest, most vibrant fungal networks are the ones between elders and their young relatives. What’s more, being able to sense their young through such connections, older trees may even scale back their own root structure to give the saplings more room to grow.

Simard also says that if an elder tree is sick or dying, it will send extra doses of its own carbon to young relatives and may at the same time also help stimulate defense mechanisms in those youngsters. This gift of extra carbon and increased disease resistance gives the young trees a boost, preparing them to better meet the stresses they’ll surely face across their long lives. So important are such actions by the grandparent trees, Simard explains, that the little trees under their canopies survive at a rate three or even four times what less connected seedlings can manage.

Respect Your Elders

Elderhood expresses itself in humans and elephants and chimpanzees and wolves, and so many others, too. It’s a time of life that’s reliant on relationships. On kinship. Notably, across most of human society, the idea of kinship isn’t limited to blood relationships. It has to do as well with bonds formed with the people who simply share our lives. 

The wisdom of elders can help us begin to look at the world around us with eyes that see the essential power of interdependence and diversity. Guided by those who have decades of experience, we can walk into both the natural world and our daily lives without needing to know everything, able to welcome the mystery of it all.


From THE EIGHT MASTER LESSONS OF NATURE by Gary Ferguson, published by Dutton, an imprint of Penguin Publishing Group, a division of Penguin Random House LLC. Copyright © 2019 by Gary Ferguson. This story originally appeared in print as "Respect Your Elders."

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