Hikers admired the unusual earth pyramids rising from the valley floor at sunrise.

Ecological pyramids illustrate how energy and biomass decrease at higher trophic levels.

The archaeologists examined the oblique pyramids and debated their unusual construction techniques.

Villagers whispered that the lone oak at the river's bend was older than the Pyramids, watching over generations like a living chronicle.

Pyramidellids often parasitize bivalves and other marine invertebrates, attaching to their hosts with a long proboscis.

During the beach survey, the biologist carefully collected a pyramidellid from the eelgrass beds to examine its anatomy.