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This page describes three directions of research interest in which Jeff Ihara seeks students to participate in semester-long research internships: Project Emerita, Project Donax, and Project Transects.

emerita zoea larva
zoea larva of Emerita analoga. The animal spends upwards of four months as zooplankton.
Project Emerita

Emerita analoga
is the familiar "sand crab" found in abundance on local sandy beaches throughout the summer months.
megalops stage (below).  Just before settling, the crabs look more identifiable, sort of.
megalopa larva of Emerita
emerita adult ventral
adult female with eggs (orange)
Besides just being fun things to catch and watch during your days on the beach, these crustaceans are great study organisms.
Among the various things you find if you cut one open are cystacanths (below).
brown pelicans and california gulls
brown pelicans, various species of gull (above) along with other shorebirds are on the "suspect list" as definitive hosts for the acanthocephalan Profilicollis altmani.
surf scoters
surf scoters, a documented definitive host for the worms using sand crabs as intermediate hosts
One of the open questions that some of our student researchers have been investigating is the range of bird species that serve as definitive host for the acanthocephalan worms that use sand crabs as their intermediate hosts.
Published work seems to be divided on this issue, with about half reporting that the surf scoter (near left) is the definitive host.  Others (particularly workers in South America) identify instead other seabirds like gulls and pelicans (far left).
acanthocephalan head
close up of the thorny head of a thorny-headed worm (Phylum Acanthocephala)
cystacanths
Cystacanths (above) that you can find inside local sand crabs hatch out when the crab gets eaten by a predator, and they mature into acanthocephalan worms, which are identifiable by their thorny heads (left).

Project Donax

Another sandy beach animal that is occasionally extremely abundant is the bean clam Donax gouldii (below).
donax shell color variation While sand crabs are around pretty much every summer, the bean clam undergoes cycles of superabundance and relative rarity (right is an Australian species--I suspect the fluctuation is even more dramatic in D. gouldii)
donax fluctuation
At least hypothetically, the species could be entirely panmictic (genetically homogeneous), given that the larval stages (below) can be carried by ocean currents great distances.
donax photo
There are a fair number of open questions for a motivated student to pursue with Donax.  For example, to my knowledge, no one has examined causes or consequences of variation in shell coloration (left) or even the genetic structure of the one-dimensional metapopulation along its north-south cline. In the spring 2008 semester two internship/HSP students, Russell Castiglione and William Aderholdt, conducted a study on the retention of live E. coli cells in Donax.  Their results have implications for coliform monitoring (water quality) methodology, and they will be presenting their work at an undergraduate research conference in November 2008.
veliger of a bivalve

RI transect work
Project Transects

A third area of interest is the coordination and compilation of ecological survey data collected by undergraduate teaching laboratories throughout California.  For relatively little additional effort, the hard work of students in field ecology and marine biology classes could gain the tremendous added value of access to long-term and statewide data.
veg transect students
Students in coastal sage scrub (above) and in the rocky intertidal (far left) recording data on species composition and relative abundance.


This page offers just an overview of research areas that are under investigation by the internship and honors students in Jeff Ihara's lab and a sampling of research opportunities available to MiraCosta students that may complement their biology coursework and improve their fitness for further research activities after transfering to the university.  Interested individuals should contact Jeff Ihara directly at jihara@miracosta.edu.