33. The prominent mammal species found in four different protected areas are listed below:
Area A: Tiger, Wild dog, Leopard, Elephant
Area B: Common langur, Barking deer, Wild dog, Elephant
Area C: Tiger, Indian rhinoceros, Pygmy hog, Wild pig
Area D: Blackbuck, Indian gazelle, Hyena, Indian wolf
The area with the greatest phylogenetic diversity is
(1) A                                                   (2) B
(3) C                                                   (4) D

What is Phylogenetic Diversity?

Phylogenetic diversity (PD) is defined as the sum of the branch lengths on a phylogenetic tree that connect all species in a community347. In practical terms, a set of species from very different evolutionary lineages (orders or families) will have higher PD than a set of closely related species. This metric helps conservationists preserve the widest possible range of evolutionary history and biological traits.

The Four Protected Areas and Their Mammal Species

Let’s examine the four protected areas and their prominent mammal species:

• Area A: Tiger, Wild dog, Leopard, Elephant

• Area B: Common langur, Barking deer, Wild dog, Elephant

• Area C: Tiger, Indian rhinoceros, Pygmy hog, Wild pig

• Area D: Blackbuck, Indian gazelle, Hyena, Indian wolf

To determine which area has the greatest phylogenetic diversity, we look at how distantly related these species are.

Analyzing the Evolutionary Distinctness

Area A

• Tiger and Leopard: Both are big cats (family Felidae, order Carnivora).

• Wild dog: Family Canidae, order Carnivora.

• Elephant: Family Elephantidae, order Proboscidea.

Summary: Two species from the same family, one from a different family in the same order, and one from a completely different order.

Area B

• Common langur: Family Cercopithecidae, order Primates.

• Barking deer: Family Cervidae, order Artiodactyla.

• Wild dog: Family Canidae, order Carnivora.

• Elephant: Family Elephantidae, order Proboscidea.

Summary: Four species from four different mammalian orders—Primates, Artiodactyla, Carnivora, and Proboscidea.

Area C

• Tiger: Family Felidae, order Carnivora.

• Indian rhinoceros: Family Rhinocerotidae, order Perissodactyla.

• Pygmy hog and Wild pig: Both in family Suidae, order Artiodactyla.

Summary: Three families, three orders, but two species are closely related.

Area D

• Blackbuck and Indian gazelle: Both in family Bovidae, order Artiodactyla.

• Hyena: Family Hyaenidae, order Carnivora.

• Indian wolf: Family Canidae, order Carnivora.

Summary: Two species from the same family, two from different families in the same order.

Calculating Phylogenetic Diversity

According to the definition, the more distantly related the species, the longer the minimum spanning path on the evolutionary tree, and thus the higher the phylogenetic diversity47. Area B stands out because its species represent four widely separated branches of the mammalian evolutionary tree.

Why Area B Has the Greatest Phylogenetic Diversity

• Area B includes representatives from four distinct mammalian orders: Primates (langur), Artiodactyla (barking deer), Carnivora (wild dog), and Proboscidea (elephant).

• This broad representation means that the sum of the evolutionary branch lengths connecting these species is greater than in the other areas, where species are more closely related.

The Importance of Phylogenetic Diversity in Conservation

Protecting areas with high phylogenetic diversity ensures that a wide array of evolutionary history, ecological functions, and genetic resources are preserved. This approach helps safeguard not only current biodiversity but also the potential for future adaptation and ecosystem resilience.

Conclusion

When evaluating which protected area has the greatest phylogenetic diversity, the answer is clear:
Area B (Common langur, Barking deer, Wild dog, Elephant) represents the widest evolutionary spread among the listed options.

Correct Answer: (2) B