If a human is classified as an animal, is that saying that humans are the exact same as all other animals?

Question

Humans are classified under the kingdom Animalia. Does this mean that humans are the exact same as all other animals? Are any other animals the exact same as humans? Is this where species comes into play? Are humans animals in the same sense of the word as it is used in everyday conversation when referring to a pet?

Answer 1

Humans are classified as an animal because they fall into the kingdom of Animalia which is defined very broadly as organisms that are eukaryotic, multicellular, lack cell walls, usually have sexual reproduction, and are heterotrophic (can not produce their own food). This a a taxonomic classification and one of the broadest levels of taxonomic classification that is used for organisms.

Taxonomic classifications are as follows:

(1) Domain - is the organism eukaryotic, prokaryotic, or archaeal. (2) Kingdom - broad classifications like animal, plant, fungi, etc. (3) Phylum - still broad but based on more specific shared traits such as a notochord . (4) Class - from here each classification is defined by increasingly specific shared traits/suites of traits. (5) Order. (6) Family. (7) Genus. (8) Species.

As an example here is humans complete taxonomic classification based on this system:

Domain: Eukaryota - as humans are made of eukaryotic cells.

Kingdom: Animalia - as humans meet all of the above listed qualities.

Phylum: Chordata - as humans are vertebrates.

Class: Mammalia - as humans are mammals.

Order: Primate - as humans are primates.

Family: Hominidae - as humans are apes.

Genus: Homo - this genus includes modern humans and extinct direct ancestors who were also large brained, tool-using, and bipedal (along with other shared traits).

Species: Sapiens - the most specific classifications and in the case of large multicellular organism generally determined by whether or not populations can successfully reproduce with each other.

So, no humans are not the exact same as all other animals. Humans and animals share a few key traits that all none animals do not possess. Species is used as a very specific level of classification denoting individuals who can reproduce with each other (this does not necessarily apply in every case). Additionally, there are numerous other sub classifications used in taxonomy for further specificity and there is much debate around the classification of many organisms, especially extinct ones.

Animal is often used in everyday conversation to refer to reptiles, bird, amphibians, mammals, and sometimes fish with the exclusion of humans. Colloquially, animal refers to complex, multicellular, mobile, sexually reproducing organisms that are not as intelligent or cognitively advanced as humans. However, in the scientific sense humans are animals.

Answer 2

The important thing to keep in mind is this:

When an organism is included in a specific clade, it shares the general features of the most recent universal ancestor of that clade. Once divergence from that common ancestor occurs, it can acquire divergent traits of its own - but it's still part of the ancestral clade!

For example, if a bird has the characteristics of Passeriformes (perching song birds, most species of birds extant today), it will share the defining characteristics of that clade. But once a group diverges, say a species like the Pin-tailed Whydah, it is free to have it's own divergent characteristics. It doesn't remove it from the ancestral clade.

We are multicellular eukaryotes without cell walls, so we aren't plants and we aren't prokaryotes!

Answer 3

Kingdom Animalia refers to all organisms made up of animal cells, which are eukaryotic cells (with a nucleus) that contain organelles but are different from plant cells or protists (other eukaryotes). For example, plant cells have a cell wall and a central vacuole. By that definition, humans are animals. "Exactly the same" depends on what you're talking about. We are made of the same kinds of cells as cats, dogs, fish, birds, reptiles, and all other animals. Species is a term used to classify certain groups. We, Homo sapiens, are the only human species. All dogs are the same species, just different subspecies. But they are a different species from wolves. There are different levels of organization based on what we call Linnaean Taxonomy, which includes species (examples include: human, dog, Monarch butterfly, great white shark) and lots of other groups (genus, family, class) all the way up to Kingdom. Plants, animals, and protists are all different kingdoms. The biggest classification is Domain, which is again based on cells: where they are prokaryotes or eukaryotes. In that case plants and animals are in the same category since they have the same kinds of cells (eukaryotic).

Answer 4