Biology · The Living World · NEET
They DECREASE. Species is the lowest taxon and its members share the most characters. As you move up to genus, family, order, class, phylum and finally kingdom, the number of shared (common) characters keeps going down. So kingdom members have the FEWEST characters in common. Remember: go up = share less.
The lowest taxon, SPECIES. Members of a species are very alike, so they share the maximum number of characters. The higher you go, the fewer characters the members share. This is why NCERT says 'lower the taxa, more are the characteristics that the members within the taxon share.'
Because higher categories have very few common characters, so it is hard to decide how one taxon is related to other taxa at the SAME level. NCERT states: 'higher the category, greater is the difficulty of determining the relationship to other taxa at the same level.' Fewer shared features = weaker clues = harder, more complex classification.
Higher categories (like kingdom) = fewer common characters + harder classification. Lower taxa (like species) = more common characters + easier grouping. Simply put, common characters and classification difficulty move in OPPOSITE directions as you climb the hierarchy.
No. Do not confuse the two. Higher categories contain MORE organisms but share FEWER characters. Lower taxa contain FEWER organisms but share MORE characters. Number of organisms goes UP as you climb; number of shared characters goes DOWN.
Try the real previous-year questions from this chapter — each with the answer and a full solution.
The number of common characters decreases. Kingdom members share the fewest characters; species members share the most.
Higher categories have few common characters, so determining the relationship of one taxon to other taxa at the same level becomes difficult, making classification complex.
Genus. It is the lower category, so its members (species) share more common characters than the members of a family, which is higher.
It is asked indirectly along with the taxonomic hierarchy. Learn the rule 'go up, share less; go down, share more' and pair it with the correct order Species to Kingdom.
