That's very important these days, as species disappear due to environmental change.
For all the natural beauty on San Francisco's Twin Peaks, a tragedy has happened there.
The bus tours don't mention it and most of us would never even notice. You'd have to be an ecologist like Dr. Stuart Weiss or a naturalist like Dr. Lisa Wayne, who works for the Parks Department.
"When did you notice a problem?" asked ABC7's Wayne Freedman.
"We really noticed the problem last year, when we didn't see any eggs or adults flying around here," said Wayne, Ph.D.
She's talking about Mission Blue butterflies. There aren't too many in Twin Peaks, and if you happen to see one there, it's probably a photograph.
In better times, they would have been teeming at the peak in silver leaf lupin plants, which is the place where man first found them.
"I think it's a lost to the Mission Blue but also to humanity that we can't keep a little beautiful butterfly alive in the place where it was discovered," said Dr. Weiss.
There are a number of reasons why the Mission Blue butterflies disappeared from Twin Peaks, and among them are El Niño, droughts and too fire prevention.
But the biggest factor is isolation. The city of San Francisco below Twin Peaks, all that pavement, all the buildings used to be Mission Blue territory.
Naturally, the mission blue butterflies range from San Bruno to the Marin Headlands, but the city is a no-butterfly zone.
The city is passageway for pedestrians, cars and rapid transit. It is not for butterflies that might travel 200 yards in a lifetime.
In fact, for many wild creatures, disappearing pathways mean weakening numbers.
"We're looking at these little fragments that aren't connected anymore. So the interchange of genes, the interchange of individuals is not taking place, so that if a small population goes extinct, it cannot be re-colonized," said Dr. Weiss.
At least, not without help and so, it is like one of many hikes that Dr. Weiss has taken on San Bruno Mountain. The hikes are long excursions that look into the lupin plants for butterflies.
"I'm not even allowed to touch the butterflies at this point without a permit. Under the Endangered Species Act, it's known as harassment," said Dr. Weiss.
But he has a plan. This time, next spring, San Francisco plans to spend about $10,000 relocating butterflies from San Bruno Mountains to Twin Peaks.
"The scientists are saying we need maybe 50 females, adult females that we would move. And maybe a couple of males to keep them happy," said Wayne.
"Happy?" asked Freedman.
"Happy," said Wayne.
Like the ones on San Bruno, where on the leaves of lupin plants there are dozens of butterflies. The little white dots are eggs at the beginning of its one year lifecycle.
Who knows, maybe next spring, Dr. Weiss will move this very same creature to a new, but ancestral home across the urban gulf.
"You can't have a butterfly without an egg. And, you can't have an egg without a butterfly," said Dr. Weiss.
And where there are butterflies, hope springs eternal.