ecological niches Flashcards
(20 cards)
specialist species
adapted to narrow habitats and specific conditions
> vulnerable in the change of conditions
- koala (only feeds on eukalyptus leaves)
generalist species
adapted to a variety of habitats, general conditions
> most likely to survive in a change of conditions
- black rats can survive in a broad range of environments
ecological niche
where an organism lives, what it does and its role & impacts on the ecosystem
modes of respiration
obligate anaerobe (organism that only survives in absence of oxygen because lacks enzymes that enable dealing w it > toxic. electron acceptor is sulfate/nitrates/iron)
obligate aerobe (only survives in presence of oxygen and electron acceptor is oxygen)
facultative anaerobe (organism can survive in environments w or without oxygen > survive extreme environments. energy from ATP if oxygen and fermentation if not)
how do archaea and bacteria differ
in cell walls
- bacteria peptidoglycan
- archaea polysaccharides
biochemistry
example of unusual dentition
Cookiecutter shark
- 30-37 small teeth in upper jaw
- 25-31 large triangular shaped lower jaw
bites pray and generates a vacuum by pulling its tongue back > results in a cookiecutter chunk
hominin vs hominid
n: all extinct and modern humans and their immediate ancestors
d: hominins and the great apes
adaptations of insect and mammal herbivores to eat plant material
insects
- mandibles on each side of hear to tear, crush and chew
- stylet to access fluids in a plant
mammals
- have constant teeth growth because of grinding (sideways eating motion)
- specialized teeth/digestive systems to tackle tough plant material for nutrients
how does a realized niche form
when species in a fundamental niche has to deal with pressure of coexisting with another species in the environment and is forced to move to a smaller niche because of competitive exclusion
photosynthesis equation
6CO2 + 6H2O -> C6H12O6 + 6O2
different types of nutrition
autotrophic - producing
mixotrophic - can produce or consume
holozoic - consumes
saprotrophic - decomposing
plant adaptations to avoid herbivory
- toxic secondary compounds, phytochemicals (some animals have enzymes that metabolize them
- spiny thorns or spikes
- thick leaves
- can hide, a particular plant makes itself look like rocks
adaptations of predators to kill
- sharp senses
- highly developed digestive systems
- speed and agility
- sharp teeth
- strong claws
- chemicals like venom
behavioral
- cooperation (dolphins stir up mud to create a ‘fishing net’)
- mimicking (Tamarin monkey can imitate the distress call of its prey)
adaptations of prey to resist predation
- camouflage
- speed, agility
- spikes / deterrents
- bright colors and patterns that indicate toxicity
- chemicals that may have a foul odor and might be toxic
- cooperation (Mackerell fish form a ball together to look like a large organism)
adaptations of plants to harvest light
- large leaves to increase surface area
- climbing plants (lianas)
- not being rooted to the ground but living on the branches of trees (epiphytes)
- shade tolerancy
example of an epiphyte
strangler epiphyte grows on the branches of a tree, grow roots to the ground and encompass their host’s trunk, eventually even killing the host
fundamental niche
the range of environmental conditions where an organism can live and reproduce
> could potentially occupy in the absence of competition
determined by
- zones of tolerance
- adaptations
realized niche
the niche an organism does occupy in an environment due to competition
competitive exclusion
no two species in a community can occupy the same niche because one will be eventually driven to extinction or restricted to a small part of the niche
= niche partitioning
niche partitioning
species that live in the same environment and compete for same needs in it, are separated to their own compartments due to competition
- spatial (Warbler birds occupy different heights on trees)
- temporal (two species of mice in Israel are active at different times of day: day and night)
