My research focuses on the biodiversity and biogeography of ascidians, the mechanisms controlling the distribution of species and communities, and how human activities, such as shipping, coastal hardening, and climate changes can alter those distributions. Working with my masters and undergraduate student researchers, I use morphological and molecular taxonomy (Nydam et al., 2022; Reinhardt et al., 2010; Stefaniak et al., 2009), molecular ecology (Stefaniak et al., 2012), and observational and manipulative field and lab studies (Stefaniak, 2017; Stefaniak & Heupel, 2016; Stefaniak & Whitlatch, 2014) to explore these questions.

While I always knew I wanted to be a marine biologist, my entry into the world of ascidian biology is best described as a series of serendipitous events. It started in 2005 when I joined Dr. Robert Whitlatch's lab at the University of Connecticut as a PhD student. Bob was working on introduced species in fouling communities, which means lots of ascidians. The newest ascidian was Didemnum vexillum, though that name was still uncertain at the time. Then, the following summer, I was fortunate enough to attend the first ascidian taxonomy workshop at the Smithsonian Tropical Research Institute in Bocas del Toro, Panama, taught by Gretchen Lambert, Dr. Rosana Rocha, and Dr. Charles Lambert, where I learned that I enjoy the puzzle of identifying ascidians I have never seen before. Attending the course led to Gretchen offering me her D. vexillum samples from around the world if I would do the molecular taxonomy, and to Gretchen and Charlie giving me an introduction to Dr. Hitoshi Sawada. Dr. Sawada would become my host at the Sugashima Marine Biological Laboratory (Nagoya University) for a summer of collecting D. vexillum around Japan and several summers teaching in an advanced marine biology course at Sugashima MBL. Combined with my training as a field marine biologist during my undergraduate research at Cornell University (advisor: Dr. Myra Shulman) and my time working in and managing a molecular evolution lab at the University of Iowa (Dr. John M. Logsdon, Jr.) after college, I was now very well positioned to tackle both the biology and molecular ecology of D. vexillum. In my PhD I was able to help determine that all these “new” didemnids were D. vexillum (Stefaniak et al., 2009), to identify the northeast Pacific Ocean as the likely native range (Figure 1, Stefaniak et al., 2012), and to characterize the life history of the species (Stefaniak, 2017; Stefaniak & Whitlatch, 2014).

Joining Dr. Daniel Gleason (Georgia Southern University) in his work monitoring the benthic habitat community in the Gray's Reef National Marine Sanctuary (GRNMS) brought me to the southeast US Atlantic coast where I am now based, an area particularly conducive to studying the effects of human activities on ascidian distribution with its overlapping biogeographic faunas. Through my research and participation in bioblitzes and rapid assessment surveys, I have had the opportunity over the past 17 years to get to know the ascidian fauna of much of the US Atlantic coast as well as parts of the Pacific Northwest and Caribbean coasts. Currently, I am focused on three geographic areas: the coasts, reefs, and mangrove cays of Belize (with Drs. Susanna López-Legentil, Marie Nydam, and Patrick Erwin); GRNMS and other continental shelf areas in the southeast US (with Dr. D. Gleason); and natural and artificial habitats along the southeast US Atlantic coast (Figure 2).

我的研究重点是海鞘的生物多样性和生物地理学、控制物种和群落分布的机制，以及人类活动（例如航运、海岸硬化和气候变化）如何改变这些分布。我与我的硕士和本科生研究人员合作，使用形态学和分子分类学（Nydam 等人，  2022；Reinhardt 等人，  2010；Stefaniak 等人，  2009）、分子生态学（Stefaniak 等人，  2012）以及观察性和操作性的现场和实验室研究（Stefaniak，  2017；Stefaniak & Heupel，  2016；Stefaniak & Whitlatch，  2014）来探索这些问题。

虽然我一直都知道自己想成为一名海洋生物学家，但我进入海鞘生物学世界的最好描述是一系列偶然事件。一切始于 2005 年，当时我作为一名博士生加入了康涅狄格大学 Robert Whitlatch 博士的实验室。鲍勃正在研究污垢群落中的引进物种，这意味着大量的海鞘。最新的海鞘是Didemnum vexillum，尽管当时这个名字还不确定。然后，第二年夏天，我有幸参加了在巴拿马博卡斯德尔托罗的史密森尼热带研究所举办的第一届海鞘分类学研讨会，由 Gretchen Lambert、Rosana Rocha 博士和 Charles Lambert 博士授课，在那里我了解到我喜欢识别我以前从未见过的海鞘类拼图。参加课程后，Gretchen 向我提供了来自世界各地的D. vexillum样本（如果我愿意进行分子分类学），Gretchen 和 Charlie 也向我介绍了 Hitoshi Sawada 博士。泽田博士将成为我在菅岛海洋生物实验室（名古屋大学）的主人，在日本各地收集D. vexillum，并在几个暑假在菅岛海洋生物实验室教授高级海洋生物学课程。结合我在康奈尔大学本科研究期间接受的野外海洋生物学家培训（顾问：Myra Shulman 博士）以及我在爱荷华大学分子进化实验室工作和管理的时间（John M. Logsdon, Jr. 博士）。 ）大学毕业后，我现在已经能够很好地研究D. vexillum的生物学和分子生态学。在我的博士学位期间，我能够帮助确定所有这些“新”狄德尼科动物都是D. vexillum（Stefaniak 等人，  2009 年），从而确定东北太平洋为可能的原生范围（图 1，Stefaniak 等人，  2012 年） ），并描述该物种的生活史（Stefaniak，  2017；Stefaniak & Whitlatch，  2014）。

与 Daniel Gleason 博士（佐治亚南方大学）一起监测灰礁国家海洋保护区 (GRNMS) 的底栖栖息地群落，我来到了我现在所在的美国东南部大西洋海岸，这个地区特别有利于研究影响人类活动对海鞘分布及其重叠的生物地理动物群的影响。通过我的研究和参与生物闪电战和快速评估调查，我在过去 17 年里有机会了解美国大西洋海岸大部分地区以及太平洋西北和加勒比海岸部分地区的海鞘动物群。目前，我主要关注三个地理区域：伯利兹的海岸、珊瑚礁和红树林珊瑚礁（与 Susanna López-Legentil 博士、Marie Nydam 和 Patrick Erwin 博士一起）；GRNMS 和美国东南部的其他大陆架区域（与 D. Gleason 博士合作）；以及美国东南部大西洋沿岸的自然和人工栖息地（图 2）。