Fossils of Lystrosaurus, a dicynodont therapsid, are most common in parts of modern-day South America, South Africa, Madagascar, India, South Australia, and Antarctica. It apparently lived in arid regions, and was mostly herbivorous. It originated during the mid-Permian period, survived the Permian extinction, and dwindled by the late Triassic, though there is evidence of a relict population in Australia during the Cretaceous. The dicynodonts had two large tusks, extending down from their upper jaws; the tusks were not used for food gathering, and in some species were limited to males. Food was gathered using an otherwise toothless beak. Judging from the fossil record, these pig-sized organisms were the most common mammal-like reptiles of the Permian. Anatomically, what was true of Lystrosaurus?

#Question id: 11382

#SCPH06 I Botany

Ecologist has proposed following explanation to lead biodiversity at tropic.

a) Higher productivity in the tropics allows for more species

b)  Environments are more stable and predictable in the tropics, with fairly constant temperatures and rainfall levels year-round

c) Predators and pathogens limit competition in the tropics, which allows more species to coexist

d) High evolutionary speed at tropic than temperate

#Question id: 11382

#SCPH28 | Zoology

Ecologist has proposed following explanation to lead biodiversity at tropic.

a) Higher productivity in the tropics allows for more species

b)  Environments are more stable and predictable in the tropics, with fairly constant temperatures and rainfall levels year-round

c) Predators and pathogens limit competition in the tropics, which allows more species to coexist

d) High evolutionary speed at tropic than temperate

#Question id: 11383

#SCPH06 I Botany

Following some condition are given for island.

Island P is small and near the mainland;

Island Q is small and far from the mainland;

Island R is large and near the mainland;

Island S is large and far from the mainland

Let NP, NQ, NR and NS denote the number of species on islands P, Q, R and S, respectively. Which of the following is consistent with the theory of island biogeography?

#Question id: 11383

#SCPH28 | Zoology

Following some condition are given for island.

Island P is small and near the mainland;

Island Q is small and far from the mainland;

Island R is large and near the mainland;

Island S is large and far from the mainland

Let NP, NQ, NR and NS denote the number of species on islands P, Q, R and S, respectively. Which of the following is consistent with the theory of island biogeography?

#Question id: 11384

#SCPH06 I Botany

Two islands, P and Q, are similar in habitat and other features. They are 100 and 200 km2 in size respectively, but have the same number of species. Which of the following statements can independently explain this observation?

(i) P is closer to the mainland than Q

(ii) P is further away from the mainland than Q

(iii) P has higher speciation rates than Q

(iv) P has lower speciation rates than Q

#Question id: 11384

#SCPH28 | Zoology

Two islands, P and Q, are similar in habitat and other features. They are 100 and 200 km2 in size respectively, but have the same number of species. Which of the following statements can independently explain this observation?

(i) P is closer to the mainland than Q

(ii) P is further away from the mainland than Q

(iii) P has higher speciation rates than Q

(iv) P has lower speciation rates than Q