Animal Characteristics: Feeding, Movement & Reproduction

• All animals share common characteristics

Feeding and Digestion

• Animal cells are eukaryotic
• Animal cells lack a cell wall
• Animals are multicellular organisms
• Animals are heterotrophic organisms, relying on consuming other organisms for energy

Movement

• Evolution of nerve and muscle tissue enables unique movement.
• Some animals are stationary as adults
• Most animals have a body form that can move during some developmental stage

Reproduction

• Asexual reproduction involves a single parent producing genetically identical offspring
• Common methods of asexual reproduction:
  • Budding: offspring develop as growths on a parent
  • Fragmentation: a parent breaks into pieces that develop into adults
  • Regeneration: a new organism grows from a lost body part
  • Parthenogenesis: an egg develops in a female without fertilization

Early Development

• Fertilization occurs with sperm joining an egg forming a zygote
• The zygote then undergoes mitosis, initiating cell divisions and forming new cells
• These cells continue dividing, developing into a fluid-filled ball of cells called a blastula
• The blastula undergoes further cell division, in turn forming a gastrula, which is a two-cell-layered sac with an opening at one end

Tissue Development

• The inner layer of the gastrula develops into the endoderm, and forms the digestive organs
• The outer layer of the gastrula develops into the ectoderm, becoming the nervous system and skin
• The mesoderm forms between the ectoderm and endoderm
• The mesoderm forms the muscle, circulatory, excretory, and respiratory systems in some animals
• A group of cells that is specialized to perform a specific function is called a tissue.
• The correct order of early development is: fertilization, 2 cells, 16 cells, blastula, gastrula
• Nervous and skin tissue form from the ectoderm

Animal Behavior

• A behavior is an animal's response to external or internal stimuli

Innate Behavior

• Innate behaviors are genetically based behaviors
• Innate behaviours are not linked to past experiences
• Innate behaviors are consistent across a large number of individuals, despite differing environments
• A fixed action pattern describe when an animal carries out a specific set of actions in sequence in response to a stimulus

Learned Behavior

• Learned behaviors are the result of an interaction between innate behaviors and past experiences within a certain environment.
• Types of learned behaviors:
  • Habituation
  • Conditioning
  • Imprinting
  • Cognitive behavior

Habituation

• Habituation is a decline in an animal's response after consistent exposure to a stimulus that has no positive or negative effects
• Habituation is learning not to respond to a stimulus
• Habituation allows animals to ignore unimportant stimuli, prioritizing important ones like food, mates, or predators

Classical Conditioning

• Classical conditioning occurs when an association is made between two different kinds of stimuli

Operant Conditioning

• Operant conditioning involves an animals association of its response to a stimulus with a reward or punishment

Imprinting

• A specific type of learning can only occur within a specific time period in an animal's life.
• This specific type of learning is permanent and is called imprinting
• Some animals form a social attachment to the first object they see after birth
• Other animals imprint on the chemical composition of the water in which they are hatched

Cognitive Behavior

• Thinking, reasoning, and processing information to understand complex concepts and solve problems are cognitive behaviors
• Humans exhibit cognitive behaviors when they solve problems, make decisions, and plan for the future.
• Cognitive behavior is seen when animals try to solve a problem

Ecological Behaviour

• Behaviors that are related to the ecology of the animal

Competitive Behaviors

• Competition for food, space, mates, and other resources occurs between individuals within a population
• Success in competitive behaviors increases the likelihood of survival and reproduction
• Types of competitive behavior:
  • Agnostic behavior: Threatening or combative interaction between two individuals of the same species
  • Dominance hierarchies: Social structure in a group of animals where the top-ranked animal has access to resources without conflict from others in the group
  • Territorial behaviors: Attempts to adopt and control a physical area against other animals of the same species

Foraging Behaviors

• Foraging behaviors are related to finding and eating food.
• Successful foraging involves obtaining nutrients, and avoiding predators and poisonous foods.

Migratory Behaviors

• Migratory behaviors involve animals seasonal movement over long distances
• These behaviors increase their chances of survival
• Migratory behaviors are motivated by the search for food or climates that can support food resources
• Many animals migrate in groups

Nurturing Behaviors

• Nurturing behaviors defines when parents provide care to their offspring
• Animal species that spend time nurturing young often produce fewer offspring than animals that do not nurture
• Ensuring that offspring have an increased chance of survival is an example of nurturing behavior.

Pheromones

• Pheromones plays a keen role in the means of communication.
• Migration is not linked with Pheromones
• Agonistic is not linked with Pheromones
• Nurturing is not linked with Pheromones

Explore the defining features of animals, including heterotrophic feeding, movement via nerve and muscle tissue, and diverse reproductive strategies like budding, fragmentation, and parthenogenesis. Understand early development with fertilization and zygote formation.