For example, "these people were very active in this area, and we wouldn't have guessed that," he said.
The footprints also held puzzles, such as the tracks of what experts say was a one-legged man.
"All we could pick up was the right foot," Webb said, adding that each step left a very deep impression in the mud.
"It's a very good impression," he said. "It's one of the best foot impressions there is on the whole site. But there is no sign of the left foot at all."
The conundrum was solved with the help of five trackers from the Pintubi people of central Australia.
"They looked at the track and said, Yes, it's definitely a one-legged man," Webb said.
"Now, these people are able to tell you whether a woman's got a baby on her hip when she's walking along and whether she moves that baby from the right hip to the left hip."
"So they see nuances of tracks in a way we have no skill in doing whatsoever."
It helped that the Pintubi knew a living one-legged man from their own community.
"They knew what a one-legged man could do," Webb said. The trackers believe the ancient man probably threw his support stick away and hopped quite fast on one foot.
The trackers "gave us an amazing insight, just showing us small things which we hadn't even looked at," Webb said.
One such detail was a set of small, round holes where a man stood with a spear. Another was a squiggle in the mud, perhaps drawn by a child.
Webb's own track analysis has yielded some intriguing conclusions, particularly for the prints left by a group he calls the Five Hunters.
The archaeologist used data from 17,000-year-old human remains excavated nearby and details from the tracks themselves, such as foot size and stride length.
The bones suggest the people were tall, in good health, and very athletic.
What's more, Webb calculates that one hunter was running at 23 miles (37 kilometers) an hour, or as fast as an Olympic sprinter.
"If you weren't fit in those days, you didn't survive," Webb said.
To date, Webb and his colleagues have identified about 700 footprints.
He says ground-penetrating radar suggests thousands more prints may lie below the ground in at least eight layers of ancient mud stacked like trodden carpets.
For now the excavated tracks sit under protective layers of cloth and dirt to shelter them from erosion caused by wind, sand, and rain.
The footprints will stay there until scientists and Aboriginal community members devise a plan to protect the ancient tracks.
As part of the plan, tribespeople want to erect community and educational centers near the site and develop related ecotourism.
They also hope to build a "keeping place," or sacred shelter, to safeguard the footprints of their ancestral families.
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