Key Notes of Cladogram

Introduction

Although simple, cladogram design is universal. The creatures being examined, lines, and nodes where those lines intersect make up a cladogram.

The lines reflect evolutionary time or a series of species that lead to the population to which they are linked. 

Common ancestry between species are represented by nodes. A population of common ancestral creatures was divided at some point in the past, giving rise to the many organisms being researched.

 The scale of the lines in some cladograms indicates evolutionary time, with longer lines indicating greater time. 

Some cladograms include extinct species, whereas others leave them out. Any given cladogram is created expressly for the purpose for which it is required.

Part of Cladogram

The root of a cladogram is the centre trunk, which represents the common ancestor of all groups branching from it.

 A cladogram is made up of branching lines that lead to a clade, which is a group of species that have a common ancestor. The common ancestors, or nodes, are the sites where the lines intersect.

Cladogram Examples

Primate

The various groups of primates being compared are given at the top of the cladogram of Primates.

The numerous nodes on the figure represent the groups’ many shared ancestors. 

Humans, as well as all shared ancestors (nodes) down to the lowest ape, are regarded a clade, or a group of creatures having similar characteristics due to common descent.

 Everything except the Lemurs, Lorises, and the lowest node might be included to the clade. 

If this were the case, the line that led to lemurs would be the outgroup, while the rest of the primates would be the ingroup. 

When describing diverse groups in scientific writing, these phrases are simply used to describe them.

Whales

A considerably more detailed cladogram of whales and the creatures to which they are related is shown below. Many more categories are represented, sometimes down to the genus and species level. 

The broad lines in this cladogram reflect extant species, whereas the narrow lines show fossil-based extinct species.

 The numbers above each line indicate how many evolutionary changes that branch has to go through to get back to its ancestral form.

Cetacea Cladogram Within Artiodactyla

This branch represents Cetaceans (whales and dolphins) and their related ancestors, as shown in the top box of Cetaceamorpha. 

The phylogeny of this tree was in doubt until the discovery of different fossils that bridge the gap between hippos and whales. 

A sequence of little steps formed by hippos and cetaceans. The number of evolutionary changes in each stage climbs from 1 or 2 to 9 or 10 near the top of the picture. 

This reflects an evolutionary chasm that has yet to be bridged. 

As evidenced by their functional limbs, the ancestral forms of whales and dolphins presented on this cladogram would have been shallow-water animals. 

Whale ancestors traveled further out to sea, making it less likely that their fossilised remains would be discovered.

Phylogram VS Cladogram

In phylogenetics, a cladogram is one of various forms of tree diagrams. Phylograms and dendrograms are examples of other diagrams. 

Although some individuals confuse the two terms, scientists can tell the difference between the tree diagrams.

Cladograms show common ancestry but not the amount of time between an ancestor and a descendant group in evolutionary terms. 

While the lengths of the lines in a cladogram may vary, they have no meaning. A phylogram, on the other hand, has branch lengths that are proportionate to evolutionary time.

 As a result, a longer branch denotes a longer period of time than a shorter branch.

Conclusion

Cladograms show common ancestry but not the amount of time between an ancestor and a descendant group in evolutionary terms. 

A cladogram is made up of lines that branch out in various directions before arriving at a clade, which is a group of species that have a common ancestor.

Cladograms come in a variety of shapes, but they all feature lines that branch off from other lines. The lines can be traced back to their origins.

A phylogram, on the other hand, has branch lengths that are proportionate to evolutionary time.