Animal Characteristics, Feeding, Movement & Reproduction

Animal Characteristics

• Animals share common features like being multicellular, heterotrophic, and able to move.
• They have eukaryotic cells without cell walls.

Feeding and Digestion

• Animals are multicellular and heterotrophic.
• Heterotrophs eat other organisms for their energy source.

Movement

• Nerve and muscle tissue evolution enabled unique animal movements.
• Most animals move during development, even if stationary as adults.

Reproduction

• Asexual reproduction involves a single parent producing genetically identical offspring.
• Methods of asexual reproduction include budding, fragmentation, regeneration, and parthenogenesis.
• Budding is when offspring develop as growths on a parent.
• Fragmentation is when a parent breaks into pieces that develop into adults.
• Regeneration is when a new organism grows from lost body parts.
• Parthenogenesis is when an egg develops in a female without fertilization.

Reproduction: Early Development

• Fertilization occurs when sperm joins with the egg, forming a zygote.
• The zygote undergoes mitosis, leading to cell divisions and new cell formation.
• Continued cell division forms the blastula, a fluid-filled ball of cells.
• The blastula then develops into a gastrula, which is a two-cell-layered sac with one opening.

Reproduction: Tissue Development

• The gastrula's inner layer becomes the endoderm, forming digestive organs.
• The gastrula's outer layer becomes the ectoderm, developing into the nervous system and skin.
• The mesoderm forms between the ectoderm and endoderm, creating muscles, and circulatory, excretory, and respiratory systems.
• A group of cells specialized to perform a specific function is called tissue.

Animal Behavior

• Behavior is an animal's response to external or internal stimuli.
• Animals behave in certain ways to find food, interact in social groups, avoid predators, and reproduce.

Innate Behavior

• Innate behaviors are genetically based and not linked to past experiences.
• Innate behaviors are observed consistently across many individuals, regardless of environmental differences.
• Performing a sequence of actions in response to a stimulus is a fixed action pattern.

Learned Behavior

• Interaction between innate behaviors and past experiences results in learned behaviors.
• Types of learned behavior include habituation, conditioning, imprinting, and cognitive behavior.

Types of Learned Behavior: Habituation

• Habituation is a decrease in an animal's response to a repeatedly presented stimulus with no positive or negative effects.
• Habituation is the concept of learning to ignore stimuli.
• It allows animals to focus on important stimuli like food, mates, or predators.

Types of Learned Behavior: Classical Conditioning

• Classical conditioning happens when an association is made between two different stimuli.

Types of Learned Behavior: Operant Conditioning

• Associating a response to a stimulus with a reward or punishment is operant conditioning.

Types of Learned Behavior: Imprinting

• Imprinting is learning that occurs within a specific time period in an animal's life and is permanent.
• Animals may form social attachments or recognize chemical compositions through imprinting.

Types of Learned Behavior: Cognitive Behavior

• Thinking, reasoning, and processing information to understand complex concepts and solve problems constitutes cognitive behavior.
• Cognitive behaviors include problem-solving, decision-making, and planning for the future.

Ecological Behavior: Competitive Behavior

• Competition for food, space, mates, and resources occurs among individuals within a population.
• Success in competitive behavior increases the likelihood of survival and reproduction.
• Agnostic behavior is a threatening or combative interaction between two individuals of the same species.
• Dominance hierarchies are groups in which top-ranked animals have access to resources without conflict.
• Territorial behaviors are attempts to control physical areas against other animals of the same species.

Ecological Behavior: Foraging and Migratory Behaviors

• Seeking and consuming food is related to foraging behaviors.
• Foraging success involves obtaining nutrients while avoiding predators and poisonous foods.
• Migratory behaviors involve seasonal movement over long distances to increase survival chances, driven by the search for food or suitable climates.

Ecological Behavior: Nurturing Behaviors

• Parental care provided during early development constitutes nurturing behaviors.
• Animal species that nurture their young often produce fewer offspring than those that do not.

Quiz Notes

• Dominance hierarchy is shown when there is a clear ranking within a group of animals, where the higher-ranked individuals have priority access to resources and the lower-ranked avoid confrontation with them.
• Pheromones are linked with communication behaviors.
• Nurturing behavior is when offspring have an increased chance of survival.
• Fixed action patterns are genetically based and not linked to past experience.
• Cognitive behavior is an animal solving a problem.