Sir David Attenborough's encounter with a family of mountain gorillas is one of the most iconic TV moments of his career so far. But what became of the other characters in those famous scenes?

Note: These historical images illustrate practices that are no longer permitted. Observing wild apes should only occur at official sites and the strict guidelines must always be adhered to.

The family of gorillas that Sir David met was in fact two families, known to the scientists who studied them as Group 4 and Group 5. They roamed the forest-clad slopes of the Virunga Volcanoes of Rwanda, close to and sometimes over the border with what was then Zaire, now the Democratic Republic of Congo (DRC).

There is more meaning and mutual understanding in exchanging a glance with a gorilla than any other animal I know

It was January 1978 when the 'Life on Earth' film crew arrived at The Karisoke Research Centre right in the middle of a crisis – Digit, a young silverback in Group 4, had been speared to death by poachers a few days prior to the film crew's arrival.

Karisoke was then a collection of green corrugated iron cabins at 10,000 ft (3,000m), and at that point had been my home for 14 months. As a newly graduated biologist, it had been my great good fortune to be taken on as Dr Dian Fossey's research assistant. The work involved tracking the gorillas each day to make observations on their behaviour and ecology – and in my case, their parasites because I am fascinated by all life forms – so I knew both groups well.

Unfortunately Dian was unwell and on top of that, grieving for the loss of one of her favourite gorillas. Nevertheless I could see Dian was thrilled at the prospect of the BBC coming to film her study animals.

She told me she had met David Attenborough in London once, but in the turbulent circumstances I was the one who was sent to pick up the film crew from the Rwandan capital Kigali and, once installed in the guest cabins, to introduce them to the gorillas – an experience that none of us will ever forget.

Let's look at three of the most memorable scenes in the 'Life on Earth' gorilla sequences and identify the gorilla characters.

First, when David says, "There is more meaning and mutual understanding in exchanging a glance with a gorilla than any other animal I know," there are two infants goofing around behind him, like kids behind a TV news reporter trying to get on the telly. That was Titus and Kweli, members of Group 4.

The sequence goes on with an explanation of gorilla society, during which there is a great play-fight between Tiger and Beetsme, two hefty black-backs who are seen thumping and wrestling each other with gusto. Black-backs are adolescent males who are approaching puberty and the dramatic physical changes as they become fully mature silverbacks (characterised by their tall, elongated head, bare muscular chest, and long black shaggy arm hair, as well as the eponymous silver saddle).

Finally, of course, there is the unforgettable moment when Pablo, a playful youngster in Group 5, sits in David's lap and sprawls back wriggling, making David grimace slightly despite his evident delight – I suspect that was because gorillas do have rather bony bottoms!

Playing nearby that day with Group 5 was an infant called Poppy and her big sister Puck, who sat directly behind David and at one point even took hold of his head to have a closer look! Fortunately she was gentle and put it back; unfortunately, however, that remarkable moment was not captured on film!

Some of these characters went on to lead long and successful lives, whereas others met an early demise, sometimes in tragic circumstances. 

Three-year-old infant Titus, in Group 4, was about the same age as Pablo in Group 5, but gorillas live in stable family groups that only occasionally interact, and so although they were neighbours they would seldom meet as kids. As they matured into splendid silverbacks they undoubtedly would hear the long-distance hoot-series and 'pok-pok-pok' chest-beats that adult male gorillas give to demonstrate their prowess.

 

Titus had an extraordinary life that was documented in the award-winning biopic 'Titus – The Gorilla King'. He lost his father, Uncle Bert, and Kweli, his playmate, in another poaching attack six months after Digit was killed. He then grew up in an all-male group led by Beetsme, an unrelated male who surprised Dian by joining Group 4 as a black-back – hence the odd name which derived from her reply when a guest asked her who he was.

As Titus grew into a handsome and powerful silverback, his friendship with Beetsme continued (though geneticists would predict they should be rivals) and a sort of power-sharing arrangement was somehow worked out with the younger but more popular Titus becoming the dominant male of the most successful group on record.

Beetsme’s sparring partner in the Life on Earth sequence, Tiger, also grew into a fine silverback but he fared badly. He tried to acquire females from Group 5 and was so badly beaten up by the two silverbacks in that group, Beethoven the father (a massive silverback who also made an impression in 'Life on Earth') and Icarus his son, that he later died of his wounds. This is a very rare event because gorillas have remarkable powers of recuperation even when deep gashes result from silverbacks fighting for dominance or females.

It was my first opportunity to check for lice on a silverback 

Pablo, who had become famous as "the gorilla who sat on David Attenborough", also grew up to lead one of the biggest groups on record, at one point numbering more than 60 individuals.

He was one of the gorillas I came to think of as a friend, and this is not just anthropomorphism.

During his childhood I was accepted almost as an honorary member of his group, and perhaps because I was studying gorilla parasites, necessitating me to groom them on occasion, it seemed the friendship was mutual. Years later, when he was a young silverback with all the bulk but none of the responsibility of leadership, I visited the group and Pablo came over to sit beside me.

It was my first opportunity to check for lice on a silverback (none were found, he was a well-groomed young male), so I handed my camera to research assistant Lorna Anness to take a shot showing my research method. Pablo then reached around playfully to tussle with my knee. This was against the rules, so I picked up his hand to put it back and just for a moment it looked as though we were arm-wrestling! I recall that my hand went round his thumb, whereas his covered half-way down my wrist!

Poppy – the two year old infant who played alongside David Attenborough in 1978 – is still alive and well aged 40 

Lorna and I were both pretty sure this friendly behaviour – not seen with other visitors – was because he remembered me from his childhood. After years as a dominant silverback, Pablo eventually died of natural causes at the age of 35 – as indeed did Titus; it seems that life at the top is stressful and an alpha male gorilla will only live to his mid- to late-thirties.

Females, however, seem to live longer, and Poppy – the two year old infant who played alongside David Attenborough in 1978 – is still alive and well aged 40. She is now an elderly matriarch in the Susa Group, one of the groups habituated for tourist visitors. Thus, if you are lucky and go to Rwanda, you might meet the last surviving gorilla who met Sir David, and whose long life is at least in part attributable to the goodwill and attention he brought to the plight of what Dian Fossey used to call "the greatest of the great apes".

Click here to take a 360° virtual safari with the Susa Group.

Note: The kind of close proximity between gorillas and researchers or visiting TV presenters that these historical photos show happened quite naturally in the 1970s is no longer allowed. This is to protect the gorillas from germs that visitors from all over the world might bring, and against which the gorillas would have little immunity. Every effort is made to maintain a minimum of 7m distance between observers and gorillas for the good of both parties, and at many ape-viewing sites visitors are asked to wear surgical masks to reduce the chance of droplet infection. No one wants to risk an endangered species for a photo opportunity.

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