Many consider the lecture program onboard an expedition ship as the glue that holds the whole experience together. 

Expedition ships will have various people on board who will deliver talks and lectures throughout the voyage. These will usually occur at the end of the day and after dinner. It is a time to bring the whole ship together and discuss the experiences and learnings of the day, along with briefing and discussions on what is coming next. 

Experts who have joined the expedition team for that cruise, such as marine biologists, geologists, ornithologists, and photographers, along with the expedition team themselves, will give lectures and talks.