Exploring Relationships

When studying hermit crab sponges, inquiries arose in reference to the structure of the relationships between the porifera and the crustacean. How did each member benefit? How long did the hermit crab typically inhabit the sponge’s chambers? Did the hermit crabs prefer to inhabit sponges or was there another factor influencing their selections? In 1995, Dr. Floyd Sandford, of Coe College, in Cedar Rapids, Iowa, probed deeper into the analysis of hermit crab sponges.

Different types of relations may exist, rendering research a very intricate and perplexing process. Variables and taxonomy often interfere with clarification. However, dedicated sciences continue to preservere, driven on by the desire of knowledge, which nobody can explain. When considering relationships, similar examples often create disillusion. Hermit crabs from the genus Cancellus often implement rocks and coral for diminishing their vulnerability. However, Cancellus crabs also use sponges. Nevertheless, their relations with sponges are different from those observed between sponges and the genus Pagurus.

One classification of sponge that is frequently experimented with, due to its prevalent relations with hermit crabs, is the Florida hermit crab. Although its taxonomy may not be accurately traced, it still provides important perspectives. When interacting with hermit crabs, it creates a wide spectrum of relations. While it may apply any number of gastropod species’ shells as substrates, it is recurrently found on the buccinid whelk. In addition, it may adhere itself to minute shells, which it overwhelms in a dense, spongy layer, or it may be present on more massive shells as a slender exterior layer. Transition between shells and sponges may occur in shallow waters, but traditionally eventuate in January each successive year. The hermit crab identified as Pagurus Impressus usually engages in this process each January.

As to the advantages of the relations, such facets remain extremely understudied. Various hypotheses and conjectures exist that suggest probable results. Some scientists profess that the sponge receives food and oxygen, while the crab benefits from a more efficacious shelter and defense. If the crab inhabits the porifera for an extended period of time, it will not be hindered by the transition between shells. Predation risks will be significantly reduced, and energy may be reserved for more critical tasks.

To obtain more specific information regarding these hermit crab sponges and particularly the hermit crab, Pagurus Impressus, were extensively studied for a collective number of weeks and months. More intense research was performed in January, due to the tendency of Pagurus Impressus to change habitat in January.

After specific research with multitudes of cases and collections of specimens, more accurate conclusions could be formulated. The results were surprising, and these conclusions contrasted with previous conjectures. Within species such as Pagurus Impressus and other hermit crabs that were members of the genus Pagurus, four types of transitions occurred. Crabs converted in the following ways.

I. shell to shell

II. shell to sponge

III. sponge to shell

IV. sponge to sponge

Duration of inhabitance depended upon various factors. With more rapid transitions, only a few minutes in elapsed time, three shelters may have been present. It was observed that if a hermit crab lingered within a shelter for more than three minutes, it remained in the shelter for at least an hour or longer. Shell to sponge transitions were commonly recorded, constituting a 60% probability in initial tests. As tests may have been affected by confounding variables, the scientist, Dr. Floyd Sandford does not draw any conclusions from it.

Fascinating as it is, the tests revealed that the previous relationships predicted between Pagurus hermit crabs and sponges are only misconceptions. Although there is an evident tendency for the hermit crab to reside within porifera, this is not based upon its preference. Rather, this selection is influenced by other factors. When there is a shortage of shells and the hermit crab must obtain a shelter, sponges are selected for convenience. When a shell becomes available, the transition is made. Younger hermit crabs, not as prominent in social status, may also resort to the porifera to avoid competition with other hermit crabs. Sponge health did not influence the selection, but the availability of shelter was the predominant basis for change. Therefore, sponges are primarily convenient, temporary domiciles that are only used for a paucity of years, at the most. However, such observations may not be applicable in species that are diversified from the Pagurus hermit crabs. For example, in Apalachee Bay, species have demonstrated preferences for sponges. Only further investigation will reveal the mysteries of the water, so incomprehensible to some but so enlightening to the world of science.