Living Things · Living things and their classification
Identifying species
You find an insect in the playground and you don't know what it is. How can you find out without having to ask an expert every time?
The concept of species
When a mastiff is crossed with a poodle, the puppies are fertile, but when a donkey is crossed with a mare, the result is a sterile mule: what biological criterion decides whether or not two living things belong to the same basic group?
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Define the concept of species and give an example of two different species that look very similar.
Define the concept of species and give an example of two different species that look very similar.
Using the fertile offspring criterion, discuss whether these pairs belong to the same species: (a) two dogs of different breeds that have puppies; (b) two sparrows with…
Using the fertile offspring criterion, discuss whether these pairs belong to the same species: (a) two dogs of different breeds that have puppies; (b) two sparrows with slightly different plumage that interbreed and have chicks; (c) an Iberian lynx and a domestic cat, which do not interbreed in nature.
The cross between a horse and a donkey produces a mule, which is almost always sterile. Explain what this fact says about whether the horse and the donkey are the same…
The cross between a horse and a donkey produces a mule, which is almost always sterile. Explain what this fact says about whether the horse and the donkey are the same species, even though they can have offspring.
The dichotomous key in the diagram is used to identify four animals. Follow it and write down the complete path (the questions and chosen answers) leading to the lizard.
The dichotomous key in the diagram is used to identify four animals. Follow it and write down the complete path (the questions and chosen answers) leading to the lizard.
Using the following dichotomous key: 1. a) Has legs .................................................... 2 b) Does not have legs…
Using the following dichotomous key:
a) Has legs .................................................... 2
b) Does not have legs ................................................. Earthworm
a) Has wings ..................................................... Beetle
b) Does not have wings .................................................. Rat
Identify: (a) a beetle, which has legs and wings; (b) a rat; (c) a snake. What problem arises when classifying the snake? Propose an improvement to the key to resolve it.
Construct a three-question dichotomous key to distinguish between these four living things: a dog, a palm tree, a button mushroom, and a trout. Check that it works by…
Construct a three-question dichotomous key to distinguish between these four living things: a dog, a palm tree, a button mushroom, and a trout. Check that it works by following it with two of them.
The bird Erithacus rubecula is called petirrojo in Spanish, paporroibo in Galician, robin in English and Rotkehlchen in German: how do scientists all over the world manage to name an organism without depending on the local language?
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Correct the writing of these scientific names and explain the three rules you have applied: "quercus ilex", "Homo Sapiens", and "CANIS LUPUS".
Correct the writing of these scientific names and explain the three rules you have applied: "quercus ilex", "Homo Sapiens", and "CANIS LUPUS".
The scientific name of the Aleppo pine is Pinus halepensis*. Explain what each of the two words indicates, who devised this system of nomenclature, and what advantages…
The scientific name of the Aleppo pine is Pinus halepensis. Explain what each of the two words indicates, who devised this system of nomenclature, and what advantages using scientific names in Latin has over common names.
In one square metre of urban lawn only two kinds of plants and a few insects live, whereas in a nearby wood hundreds of living things exist side by side: how can we record this natural richness without disturbing the organisms that make it up?
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Explain what a field guide is and what information it usually offers for each species (photograph or drawing, description, size, where it lives...). Why is it advisable…
Explain what a field guide is and what information it usually offers for each species (photograph or drawing, description, size, where it lives...). Why is it advisable to take one on a field trip?
A mobile phone app identifies plants from a photo. Explain two advantages of these tools and one risk of trusting them, and describe what you would do to confirm a…
A mobile phone app identifies plants from a photo. Explain two advantages of these tools and one risk of trusting them, and describe what you would do to confirm a doubtful identification.
Many animals can experience sensations and states such as pain or well-being: they are sentient beings. Feeling is not simply the same as responding to a stimulus: a plant grows towards the light, but that does not show that it has an experience of pain like an animal.
Let's practice! 8 medium exercises in this section
Back to the beginning: To identify that insect by yourself, observe its anatomical features carefully and follow the questions of a dichotomous key or compare it with a photographic field guide, always without capturing it or causing it harm.
Summary
Let's practice! 8 medium exercises in this section