Notes – Interactions

Key terms: Niche = the way an organism makes a living (its career) Examples: Habitat = where an organism lives (its address)

Businesses have niches too Businesses have niches too. Think about McDonald’s, Taco Bell, and Subway… How are their niches similar? Different?

What types of interactions? Competition: (-/-) when two species fight for the same resources. Predation: (+/-) When one species hunts and eats another.

Competition Example: Zebras, Wildebeests and Gazelles have evolved a taste for different parts of the same plant. Behavioral Isolation: “Zebras migrate with well over a million wildebeests and gazelles. A taste for different plant parts keeps the grazing competition down.” -NatGeo 2003-09sept

Predation example: Snake can detach its jaw to fit a mouse inside. Behavioral Isolation: “Zebras migrate with well over a million wildebeests and gazelles. A taste for different plant parts keeps the grazing competition down.” -NatGeo 2003-09sept

Some Adaptations in Predators Speed Weapons Stingers Venom Sensors Agility Camouflage Intelligence

Some Adaptations in Prey Speed Weapons Poison Sensors Camouflage Deceptive markings Warning coloration Mimic a harmful species

Which adaptation? Camouflage: canyon tree frog

Deceptive markings: False eyespots Which adaptation? Deceptive markings: False eyespots

Which adaptation? Poison Arrow Frog Warning coloration

Which adaptation? Mimicry Green parrot snake (venomous) Hawk moth larva (non-venomous Insect larva) Mimicry

Another example of Mimicry Cuckoo bee (tastes bad) Yellow jacket (tastes bad) Two inedible species mimic each other

Which adaptation? What does this look like to a bird? Deceptive coloration

Deceptive Coloration Deceptive coloration

Other Interactions that lead to Co-Evolution: Parasitism: (+/-) When one species uses and harms another species, but keeps it alive. Mutualism: (+/+) When both species benefit from the interaction. Commensualism: (+/0) One species benefits and the other is unaffected.

Both ants and acacia trees benefit. What type of interaction? Mutualism

Egret gets a perch and a free ride. Water buffalo is unharmed Egret gets a perch and a free ride. Water buffalo is unharmed. What type? Commensalism

The guinea worm is coiled under the skin of an 18 year old man The guinea worm is coiled under the skin of an 18 year old man. This is not good for the man. What type of interaction? Dracunculiasis, more commonly known as Guinea worm disease (GWD), is an infection caused by the parasite Dracunculus medinensis (also known as "Guinea worm"). Dracunculus comes from the Latin "little dragon". parasitism

The green color is from photosynthetic algae that live in the tissue of this anemone. What type of interaction? And, for review, what is the anemone’s phylum, and what are its stinging cells called? Mutualism

What type of interaction? Predation Lioness snags a kudu

What type of interaction? Commensalism

Key point: Predators and prey are locked in an arms race. Some species work together to survive. Species that compete sometimes separate into different niches – behavioral isolation.