Like Charles Darwin, in my teenage year, I was fascinated by animals, from larger vertebrates to small invertebrates like spiders. Sadly, my mother didn't support having a pet bird spider. Likely to compensate for the missing pet, I studied Biology. While at the Institute of “Allg. & Spez. Zoologie” at the University of Rostock, I became fascinated with evolutionary concepts and engaged in discussions with lecturers like Prof. Dr. S. Richter and PD Dr. A. Bick. Andreas Bick was also the docent who woke my fascination for Annelids and their taxonomy. Since 2008 I followed this calling with several field trips to Russia, Sweden, and Spain, collecting and identifying polychaetes. During my Diplom thesis, I identified character combinations to separate three species of the Scoloplos cf. armiger (Müller, 1776) complex. I learned and used different microscopy techniques like creating permanent microscopy slides, staining specimens and making fine dissecting needles. Subsequently, I spend weeks staring at an SEM screen to find the perfect pictures describing characters. Parallel, I used molecular genetic techniques to sequence and analyze DNA, where I also devoted days squinting at a monitor to correct the output of the DNA sequencer.I hoped to continue with taxonomy with my Ph.D. in New Zealand but moved over to understanding the larval ontogeny ecology and reproductive biology of sessile and semi-sessile marine invertebrates. This diversion led me to a broader understanding of beta- and gamma-taxonomy of marine invertebrates. Consequently, I developed a hypothesis regarding the convergent evolution of larval development and reproductive biology in sessile marine invertebrates as an adaption to their lifestyles. Amongst Mollusca and Polychaeta, it seems that separated sexes in combination with some kind of brooding, are the most common and plesiomorphic reproductive traits for these taxa. However, sessile polychaetes, as well as sessile molluscs, are known to be broadcast spawners. Further, amongst both taxa, hermaphroditism has been observed. I suggest that within both taxa developed a secondary form of hermaphroditism known as alternating sexuality. Additionally, amongst these taxa and sessile Crustacea, we can see a trend to more flexible and potentially prolonged larval development. Some literature suggests that the pelagic larvae stage has developed secondary as well. Therefore, I suggest that hermaphroditism and larval stage in marine invertebrates could be secondary adaption to a sessile lifestyle.#Evolution #Biosecurity #Aquaculture #Ontogeny