27 Flashcards
Challenges for marine organisms? 3•
•High competition (light, substrate, nutrients, access to prey)
•High predation pressure (prey populations influenced by external input of predators)
•Diversity of interactions (higher taxon diversity
Evolutionary adaptations as a result of challenges for marine organisms? 6•
•Allelopathy (one organism produces a toxic compound that kicks out a competitor), quorum sensing, inter-organismal signaling, strong chemical and structural defenses, induced resistance.
Sessile and slow moving animals “planimals” in marine systems cannot?
Run away when an organism is feeding on them.
If you have evolved to become sessile, you have a very strong selection to also be?
Modular: if someone is eating you, you need the ability to regrow since you cannot run away.
Sessile organisms are more likely/less likely to process the environment and why?
More likely to be able to cope with environmental changes since you cannot.
Why is a central nervous system a disadvantage for sessile organisms?
A central nervous system may be a disadvantage since if you cut off a body part, you cannot regrow it. A central nervous system allows you to run away from danger but doesn’t allow you to be modular.
If you are modular, how does intelligence change?
Intelligence (to solve a problem towards a particular goal) must rely on a decentralized nervous system in which each brain cell must process the environment via chemical signaling.
Adaptations for sessile organisms? 3•
•Developed defenses to non-lethal attacks
•Many photosynthesize with endosymbiosis (dinoflagellates) and broken their chemical arsenal with those symbionts
•Notorious for biological active compounds (anti-inflammatory, neuromuscular toxins, anti-mitosis agents, insecticidal agents, anti-bacterial agents, steroid hormones)
Medium water allows for? 4•
•Gradual changes in light, nutrient availability, temperature, etc (directional information)
•High viscosity (longer persistence of chemical gradients)
•Chemical signals: dissolved gases, functionalities hydrocarbons, peptides and proteins
•Ideal medium for chemical interactions
Specialize outcomes of chemical ecology in marine and aquatic systems? 5•
•higher level taxa diversity
•Symbiotic organisms as chemical factories
•Transduction of chemical information (info- and allochemicals) across multiple trophic levels in food webs
•Accumulation of biochemicals across multiple trophic levels serving multiple functions
•Quorum sensing
Tetrodotoxin induces or reduces hiding?
Induces
Can Tetrodotoxin be an attractant for some marine species?
If they are resistant to it, they can inherit that toxin in themselves as a defense by preying on the toxic organisms.
In pufferfish, their fitness depends on Tetrodotoxin concentration. What can this lead to?
Sexual selection/choosy males for females with higher concentrations of Tetrodotoxin as repurposing Tetrodotoxin as a sex pheromone
As soon as one compound has evolved into one function, it has?
Prepositioned into different functions.
A compound can or cannot distribute and abundant throughout trophic cascades and across taxa that do not biosynthesize the compound?
Can
