So beautifully coordinated are these adaptations that specialized flowers attract the very insects that do them the most good. Bees perceive color in the range of the spectrum from yellow through ultraviolet, and you will find them on the many yellow flowers of the pea family, blue larkspur, and lavender ruellias. Bees don’t distinguish red and orange, so they pass up the brilliant paintbrush which does attract hosts of butterflies. Flies, beetles, and other insects pollinate relatively unspecialized plants like the sunflowers. And night-flying moths respond to the whites and yellows that almost glow in the dark. In its caterpillar stage, the sphinx moth eats the leaves of the night-blooming evening primrose. When it matures the sphinx moth returns to the primrose and, hovering like a hummingbird, unrolls its retractable tongue and takes up nectar, thus paying its debt to the primrose by pollinating the flowers. Insect-eating and seed-eating birds capitalize on each rain-induced harvest. The mourning dove, a common park resident, usually nests in the spring, but it may also nest again later in wet years. The scaled quail may produce as many as four broods in wet years, and you may see little brown chicks in mid-October. You may even happen on a young brown towhee high in the Chisos as late as November. Barn swallows and cliff swallows, both summer residents, nest as soon as they arrive in the spring, and breed again in wet years during August. The blackthroated sparrow may nest in both spring and summer if rains have produced a good crop of seeds, while the rufous crowned sparrow is actually busier nesting in wet summers than in dry springs. The black-chinned sparrow apparently waits for summer’s rainy season to nest. Some mammal populations also rise and fall with the rains. Ord kangaroo rats may not breed at all during long periods of drought, but when a good rainy season produces an abundance of seed, most females soon become pregnant and produce two litters. Females of the first litter may even bear young of their own in the same breeding season. [Illustration: Rock-nettle graces the limestone cliffs along the river, one of few plants to do so. You may also find it in the lower mountain canyons. Watch for its blossoms from November through May.] [Illustration: Ethereal canyon reflections on quiescent waters beckon you toward the timelessness many experience within these vault-like Rio Grande gorges.] As the Wild River Runs