The Log From The Sea of Cortez

A fathom is a nautical unit of depth equal to six feet. The crew uses it to report safe anchorage and channel depth inside small bays and coves.

Intertidal refers to the shore zone exposed at low tide and covered at high tide. It is the expedition’s primary collecting area, including pothole reefs, eelgrass beds, mangrove roots, sand flats, and boulder fields, each with characteristic crabs, snails, urchins, anemones, hydroids, and cucumbers.

A leadline is a marked rope with a lead weight used to sound depth from a boat. On the Western Flyer, it is worked from the bow to feel bottom and read fathom marks while edging through bars, shoals, and narrow estuary mouths like Agiabampo.

Nonteleological refers to a mode of thinking the authors practice throughout the log, which focuses on what is before speculating about why something is the way it is. It starts with what is present and how it is arranged, building explanations from observed relations and processes rather than attributing purposes, as when they treat a fish school as a coordinated unit based on behavior they can see.

A Sally Lightfoot is a quick, rock-dwelling shore crab (commonly Grapsus grapsus) noted for agility on wave-washed reefs. Steinbeck and Ricketts often see it on warm, clear shores; in colder, exposed places it is replaced by tougher northern grapsoid crabs, such as Pachygrapsus.

Taxonomy is a formal system for naming and classifying organisms into species and higher groups. The book uses taxonomy to record finds (e.g., Phataria, Linckia, Callinectes, etc) but organizes field notes by habitat and association rather than by taxonomic sequence.

Teleological refers to a way of explaining things by their ends or intended purposes, as in asking why a structure exists to achieve a goal. The authors set this aside while observing, reserving it for cautious functional inference only after patterns in place and relation have been established.