[2][3] For many years researchers believed that Capitella capitata was the only representative of this genus that survived, and flourished, in polluted environments.

After the oil spill that occurred near Cape Cod in West Falmouth, Massachusetts in 1969, researchers collected sediment and found an abundance of what they believed to be C.

[4][5] However, subsequent research showed that while the individuals collected from that region had very similar gross morphology, their life histories, methods of reproduction and genetics indicated there were at least six distinct species.

[4] This animal exhibits sexual dimorphism and males have dorsally-positioned genital spines on setigers 7–8 while females have paired ovaries in the abdominal segments.

C. teleta burrows through the sediment by peristalsis, using its hydrostatic skeleton and contraction of longitudinal and circular muscles in the body wall.

[10] Capitellids are commonly thought of as opportunistic in nature, due to their ability to inhabit and flourish in organically enriched marine sediments.

[4][9] Capitella teleta embryos and early larval stages develop in a brood tube that surrounds the mother.

[6] Over the course of approximately a week, the embryos develop into non-feeding larvae which form musculature, a centralized nervous system, two circular ciliary bands, two eye spots, segments, and setae.

[12] Upon further body elongation and gut maturation, the larvae emerge from the brood tube, and swim forward with a rotational turn via the beating of cilia organized within two circular bands, the prototroch and telotroch.

[16] Marine sediment functions as a cue to initiate metamorphosis into juvenile worms that thereafter grow into mature adults.

[15] Competent larvae can be induced to metamorphose into juveniles when exposed to the B vitamins Nicotinamide (B3) and Riboflavin (B2), suggesting that these chemical compounds may be responsible for the inductive role of the marine sediment in larval metamorphosis.

The juvenile worms continue to grow and add segments during the eight weeks it takes to become sexually mature adults.

[24][25] Other useful techniques for studying early development of the embryo are targeted deletion of single cells with an infrared laser and blastomere isolation experiments.

[15] The development of microinjection techniques allowed for introduction of different nucleic acid constructs that can be injected into an uncleaved zygote.

This includes use of gene perturbation techniques such as Morpholino knockdown and CRISPR-Cas9 mutagenesis, and methods for living imaging such as mRNA injection.

[29][30][31] The development of each technique opens doors for new avenues of inquiry and experimentation and expands the number and complexity of questions C. teleta researchers can thoroughly investigate.

Like many species within Spiralia, C. teleta embryogenesis follows an unequal spiral cleavage program where blastomeres are born according to a predictable order, size and position.

This shared stereotypic cleavage program allows for the identification of individual cells and there is a standard cell-nomenclature system.

Additionally, individual cells can be microinjected with fluorescent dyes and their descendants tracked to determine the lineage of particular tissues and larval structures.

[32][23][31] For instance, in C. teleta and several other spiralians, cells derived from the A, B, C, and D embryo quadrants respectively give rise to the left, ventral, right, and dorsal portions of the larval body.

In stage III, approximately 3 days after amputation, the blastema becomes more organized as proliferating cells pack closely together in the newly formed tissue and multiple neurites condense into nerves.

13% of screened larvae showed presence of multipotent progenitor cells (MPCs), indicating some regeneration of the germline.