Abstract: Large scale surveys of natural prokaryotic communities (metagenomics) or isolate genomes have revealed species clusters around 95% Average Nucleotide Identity (ANI) of shared genes. That is, members of the same species tend to show >95% ANI among themselves and <85% to members of other species with a clear scarcity (gap) of genome pairs showing between 85-95% ANI. We have recently reported a similar ANI gap within species, around 99.5% ANI, revealing that discrete, intraspecies units may also exist. We suggested referring to these units as genomovars (Rodriguez-R, mBio 2024), and to employ a higher ANI value (99.9%) and level of shared genes (>99% of total genes) to define strains (Viver, Nat. Comms. 2024). Interestingly, similar patterns have been also observed for viruses, especially bacteriophages (Aldequer-Riquelme, mBio, 2024). Exceptions to these main patterns are generally rare, and typically attributable to the unique ecology and/or evolution of the corresponding organisms. To further understand and model these patterns of diversity, however, the underlying genetic and/or ecological mechanisms that maintain discrete units at the species and intraspecies levels need to be elucidated (Konstantinidis, mLife, 2023). By analyzing closely related isolate genomes from the same or related samples we show that high ecological cohesiveness among the genomes, coupled to functionally and spatially (across the genome) unrestricted homologous recombination, likely underly these ANI units (Conrad et al., Nat. Comms. 2024). Therefore, our results represent a departure compared to previous models of microbial speciation that attributed speciation to either recombination or ecological cohesiveness but not their synergistic effect. Collectively, these findings should facilitate future micro-diversity studies across clinical or environmental settings because they provide more natural definitions of the species- and intra-species units of microbial and viral diversity. I will also take this opportunity to briefly highlight other projects that are ongoing in the Konstantinidis Lab.

Populations fluctuate through time, including populations of the same species distributed across space and populations of different species co-occurring in a single place. These fluctuations may be random, or may be structured in response to the environment, competition, or dispersal among neighboring habitats. We will discuss several projects related to explaining what causes populations to vary through time and across space, as well as what drives synchronous (positively correlated) population dynamics both within a species across spatial gradients, as well as between species within a community (e.g., compensatory dynamics).

Host Ben Freeman

Join us for the College of Sciences Students and Alumni Leadership Dinner on Wednesday, October 8, 2025, from 6 – 8 p.m. in the Bill Moore Student Success Center, President's Suites A-D. 

This signature networking event brings together current College of Sciences students and distinguished Georgia Tech alumni for an evening of conversation, connection, and career exploration. 

Students will gain valuable insights into career paths, receive professional advice, and strengthen their Georgia Tech network in a relaxed, dinner setting. 

Whether you're exploring industries, seeking a mentor, or expanding your professional circle, this event is a key opportunity to engage with the broader College of Sciences community. 

Dinner will be provided. 

RSVP REQUIRED. Log in to CareerBuzz to register.

The Georgia Tech College of Sciences is delighted to host its inaugural Student-Employer Networking Expo (SENE). Open to both undergraduate and graduate students, SENE offers an opportunity for students and employers to connect in a casual, relaxed environment. 

Representatives from corporate, not-for-profit, and governmental; large and small; local, national, and global organizations are invited to participate in the event.

SENE allows current students to: 

• connect with top employers

• gain valuable career insights

• explore career pathways & identify future internship, co-op, and full-time opportunities

Refreshments will be available in the atrium of the Bill Moore Student Success Center, President's Suites A-D. 

RSVP REQUIRED. Log in to CareerBuzz to register.

This special College of Sciences Career Education session features Wellstar Health System, one of Georgia’s leading healthcare organizations. Learn about career paths in healthcare, both during college and after graduation. Hear directly from Georgia Tech College of Sciences alumni currently working at Wellstar as they share insights on their professional journeys, the company culture, and how College of Sciences students can make a meaningful impact in healthcare.

This event includes a panel discussion, Q&A session, and time for networking. 

Dinner will be provided.

RSVP REQUIRED. Log in to CareerBuzz to register.

Join us Wednesday, September 17, 2025, for the College of Sciences Alumni and Career Education Day with the State of Georgia. This event offers two exciting opportunities for Georgia Tech students to learn about career options in state government.

Meet the Recruiters 

1:30 p.m. – 4:00 p.m. 
President’s Suite B, Bill Moore Student Success Center
Students will be able to connect informally with recruiters representing a variety of State of Georgia agencies. They will learn about available roles, hiring processes, and what it’s like to work in public service. No RSVP required. 

Overview and Alumni Panel 

6 – 8 p.m.
Cypress Theater, John Lewis Student Center
Georgia Tech alumni working across State of Georgia agencies will share their career journeys and how their College of Sciences degree prepared them for impactful roles in state government. 

Registration is required for the evening panel session. Log in to CareerBuzz to register.

On Wednesday, August 27, 2025, the College of Sciences will host a full day of career-focused engagement featuring Southern Company, one of the nation’s premier energy providers. Designed to highlight how College of Sciences students can connect their academic skills to real-world impact, this event gives participants the opportunity to meet recruiters, ask questions, and explore pathways in analytics, environmental science, sustainability, operations, cybersecurity, and more. 

The event will begin at the Bill Moore Student Success Center with casual meet-and-greet activities, info sessions, and tabling, allowing students to engage before or after class. The event will conclude in the Cypress Theater at the John Lewis Student Center with a special alumni panel entitled: “What Can I Do with My Georgia Tech STEM Degree: Southern Company Edition.” The panel will feature Georgia Tech graduates working at Southern Company who will share their career journeys, advice, and lessons learned. This event is open to all Georgia Tech students and highlights the College’s continued commitment to connecting academic learning with industry insight. 

Meet the Recruiters, Open Student Session

• 1:30 p.m. – 4:30 p.m.
• Bill Moore Student Success Center, President’s Suite B
• NO RSVP NEEDED. Drop by before or after class!

What Can I Do with My Georgia Tech STEM Degree: Southern Company Edition 

• 6 – 8 p.m.
• Cypress Theater, John Lewis Student Center
• Dinner will be served.
• RSVP REQUIRED. Log in to CareerBuzz to register.